camel-quarkus-xslt-saxon does not support extension functions in native mode

### Bug description

Currently the saxon extension function does not support in native mode. It throws some error message at build time if we want to generate an class for the template. Something like
```
2023-08-14 13:18:24,583 ERROR [org.apa.cam.qua.com.xsl.CamelXsltErrorListener] (build-2) The first argument to the non-static Java function 'myExtensionFunction1' is not a valid object reference.: javax.xml.transform.TransformerException: The first argument to the non-static Java function 'myExtensionFunction1' is not a valid object reference.
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.passErrorsToListener(TransformerFactoryImpl.java:661)
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:836)
at org.apache.camel.quarkus.support.xalan.XalanTransformerFactory.newTemplates(XalanTransformerFactory.java:70)
at org.apache.camel.quarkus.component.xslt.deployment.XsltProcessor.xsltResources(XsltProcessor.java:117)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at io.quarkus.deployment.ExtensionLoader$3.execute(ExtensionLoader.java:864)
at io.quarkus.builder.BuildContext.run(BuildContext.java:282)
at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)
at java.base/java.lang.Thread.run(Thread.java:833)
at org.jboss.threads.JBossThread.run(JBossThread.java:501)

2023-08-14 13:18:24,586 ERROR [org.apa.cam.qua.com.xsl.CamelXsltErrorListener] (build-2) The first argument to the non-static Java function 'myExtensionFunction2' is not a valid object reference.: javax.xml.transform.TransformerException: The first argument to the non-static Java function 'myExtensionFunction2' is not a valid object reference.
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.passErrorsToListener(TransformerFactoryImpl.java:661)
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:836)
at org.apache.camel.quarkus.support.xalan.XalanTransformerFactory.newTemplates(XalanTransformerFactory.java:70)
at org.apache.camel.quarkus.component.xslt.deployment.XsltProcessor.xsltResources(XsltProcessor.java:117)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at io.quarkus.deployment.ExtensionLoader$3.execute(ExtensionLoader.java:864)
at io.quarkus.builder.BuildContext.run(BuildContext.java:282)
at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)
at java.base/java.lang.Thread.run(Thread.java:833)
at org.jboss.threads.JBossThread.run(JBossThread.java:501)

2023-08-14 13:18:24,586 ERROR [org.apa.cam.qua.com.xsl.CamelXsltErrorListener] (build-2) The first argument to the non-static Java function 'myExtensionFunction2' is not a valid object reference.: javax.xml.transform.TransformerException: The first argument to the non-static Java function 'myExtensionFunction2' is not a valid object reference.
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.passErrorsToListener(TransformerFactoryImpl.java:661)
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:836)
at org.apache.camel.quarkus.support.xalan.XalanTransformerFactory.newTemplates(XalanTransformerFactory.java:70)
at org.apache.camel.quarkus.component.xslt.deployment.XsltProcessor.xsltResources(XsltProcessor.java:117)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at io.quarkus.deployment.ExtensionLoader$3.execute(ExtensionLoader.java:864)
at io.quarkus.builder.BuildContext.run(BuildContext.java:282)
at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)
at java.base/java.lang.Thread.run(Thread.java:833)
at org.jboss.threads.JBossThread.run(JBossThread.java:501)

2023-08-14 13:18:24,587 ERROR [org.apa.cam.qua.com.xsl.CamelXsltErrorListener] (build-2) Could not compile stylesheet: javax.xml.transform.TransformerConfigurationException: Could not compile stylesheet
at org.apache.xalan.xsltc.trax.TransformerFactoryImpl.newTemplates(TransformerFactoryImpl.java:832)
at org.apache.camel.quarkus.support.xalan.XalanTransformerFactory.newTemplates(XalanTransformerFactory.java:70)
at org.apache.camel.quarkus.component.xslt.deployment.XsltProcessor.xsltResources(XsltProcessor.java:117)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at io.quarkus.deployment.ExtensionLoader$3.execute(ExtensionLoader.java:864)
at io.quarkus.builder.BuildContext.run(BuildContext.java:282)
at org.jboss.threads.ContextHandler$1.runWith(ContextHandler.java:18)
at org.jboss.threads.EnhancedQueueExecutor$Task.run(EnhancedQueueExecutor.java:2513)
at org.jboss.threads.EnhancedQueueExecutor$ThreadBody.run(EnhancedQueueExecutor.java:1538)
at java.base/java.lang.Thread.run(Thread.java:833)
at org.jboss.threads.JBossThread.run(JBossThread.java:501)

```

Start by tracing the native build failure from org.apache.camel.quarkus.component.xslt.deployment.XsltProcessor.java through org.apache.camel.quarkus.support.xalan.XalanTransformerFactory.java. Reproduce the reported Saxon extension-function failure in native mode, then verify that the stylesheet compiles and extension functions work without the build-time errors shown.

Written by the indexing model from the issue text.