DynamoDB Enhanced Client shouldn't assume every method is a property

### Describe the bug

When using `@DynamoDbImmutable`, the mapper throws an exception if _any_ custom non-property method exists.

In the specific case of Groovy's `@groovy.transform.EqualsAndHashCode`, an entirely innocent method `@Generated public boolean canEqual(Object)` is created, and the mapper throws. Note that as this is a generated method, I don't even have the opportunity to annotate it.

### Expected Behavior

I expected a plain (_generated_) method that does not map as a JavaBeans getter to be ignored by the mapper.

### Current Behavior

```
java.lang.IllegalArgumentException: A method was found on the immutable class that does not appear to be a valid getter due to it having one or more parameters. Use the @DynamoDbIgnore annotation on the method if you do not want it to be included in the TableSchema introspection. [Method = "public boolean com.example.MyRecord.canEqual(java.lang.Object)"]
at software.amazon.awssdk.enhanced.dynamodb.internal.immutable.ImmutableIntrospector.generateExceptionForMethod(ImmutableIntrospector.java:134)
at software.amazon.awssdk.enhanced.dynamodb.internal.immutable.ImmutableIntrospector.validateGetter(ImmutableIntrospector.java:156)
at software.amazon.awssdk.enhanced.dynamodb.internal.immutable.ImmutableIntrospector.lambda$introspect$2(ImmutableIntrospector.java:82)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1655)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578)
at software.amazon.awssdk.enhanced.dynamodb.internal.immutable.ImmutableIntrospector.introspect(ImmutableIntrospector.java:93)
at software.amazon.awssdk.enhanced.dynamodb.internal.immutable.ImmutableIntrospector.getImmutableInfo(ImmutableIntrospector.java:65)
at software.amazon.awssdk.enhanced.dynamodb.mapper.ImmutableTableSchema.createStaticImmutableTableSchema(ImmutableTableSchema.java:168)
at software.amazon.awssdk.enhanced.dynamodb.mapper.ImmutableTableSchema.create(ImmutableTableSchema.java:139)
at software.amazon.awssdk.enhanced.dynamodb.mapper.ImmutableTableSchema.recursiveCreate(ImmutableTableSchema.java:162)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.convertTypeToEnhancedType(BeanTableSchema.java:301)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.staticAttributeBuilder(BeanTableSchema.java:250)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.lambda$createStaticTableSchema$2(BeanTableSchema.java:205)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.createStaticTableSchema(BeanTableSchema.java:193)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.create(BeanTableSchema.java:138)
at software.amazon.awssdk.enhanced.dynamodb.mapper.BeanTableSchema.create(BeanTableSchema.java:129)
at software.amazon.awssdk.enhanced.dynamodb.TableSchema.fromBean(TableSchema.java:83)
at software.amazon.awssdk.enhanced.dynamodb.TableSchema.fromClass(TableSchema.java:126)
```

### Reproduction Steps

```
@DynamoDbImmutable(builder = Builder)
@EqualsAndHashCode
class MyRecord {
String channel

static class Builder {
String channel
MyRecord build() { new MyRecord(channel) }
}
```

### Possible Solution

`ImmutableIntrospector` should not assume in `filterAndCollectGetterMethods` and `isMappableMethod` that every method is a property getter.

### Additional Information/Context

_No response_

### AWS Java SDK version used

2.19.25

### JDK version used

openjdk version "11.0.11" 2021-04-20 OpenJDK Runtime Environment AdoptOpenJDK-11.0.11+9 (build 11.0.11+9) OpenJDK 64-Bit Server VM AdoptOpenJDK-11.0.11+9 (build 11.0.11+9, mixed mode)

### Operating System and version

Gentoo Linux