Backtrace gson serialization bug

```
2021-02-14 18:11:06.604 [backtrace-daemon] ERROR backtrace.io.Backtrace - Exception during pipeline for message from queue..
java.lang.reflect.InaccessibleObjectException: Unable to make field private java.lang.String java.lang.Throwable.detailMessage accessible: module java.base does not "opens java.lang" to module com.google.gson
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:349) ~[?:?]
at java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:289) ~[?:?]
at java.lang.reflect.Field.checkCanSetAccessible(Field.java:174) ~[?:?]
at java.lang.reflect.Field.setAccessible(Field.java:168) ~[?:?]
at com.google.gson.internal.reflect.UnsafeReflectionAccessor.makeAccessible(UnsafeReflectionAccessor.java:44) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:159) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.getAdapter(Gson.java:458) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.getAdapter(Gson.java:458) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166) ~[gson-2.8.6.jar:?]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.getAdapter(Gson.java:458) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.toJson(Gson.java:696) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.toJson(Gson.java:683) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.toJson(Gson.java:638) ~[gson-2.8.6.jar:?]
at com.google.gson.Gson.toJson(Gson.java:618) ~[gson-2.8.6.jar:?]
at backtrace.io.helpers.BacktraceSerializeHelper.toJson(BacktraceSerializeHelper.java:21) ~[backtrace-java-0.9.1.jar:?]
at backtrace.io.http.ApiSender.sendReport(ApiSender.java:29) ~[backtrace-java-0.9.1.jar:?]
at backtrace.io.Backtrace.sendReport(Backtrace.java:98) ~[backtrace-java-0.9.1.jar:?]
at backtrace.io.Backtrace.processSingleBacktraceMessage(Backtrace.java:75) ~[backtrace-java-0.9.1.jar:?]
at backtrace.io.Backtrace.handleBacktraceMessage(Backtrace.java:44) [backtrace-java-0.9.1.jar:?]
at backtrace.io.BacktraceThread.run(BacktraceThread.java:56) [backtrace-java-0.9.1.jar:?]
```