"graphql-java-extended-scalars" is not a valid module name

[draftcode]

Describe the bug
A clear and concise description of what the bug is.

Automatic-Module-Name is specified in the manifest, but it is an invalid module name. Because of this, while I haven't articulated on what condition this triggers, a compilation error happens.

To Reproduce

To check the module validity:

$ wget https://repo1.maven.org/maven2/com/graphql-java/graphql-java-extended-scalars/18.1/graphql-java-extended-scalars-18.1.jar
$ jar --describe-module --file graphql-java-extended-scalars-18.1.jar
Unable to derive module descriptor for: graphql-java-extended-scalars-18.1.jar
Automatic-Module-Name: graphql-java-extended-scalars: Invalid module name: 'graphql-java-extended-scalars' is not a Java identifier

I tried to create a minimal case for the compilation error, but cannot trace down what triggers an error.

---

As for the module name's specification, I think this part is the relevant part:

https://docs.oracle.com/javase/specs/jls/se9/html/jls-7.html#jls-7.7

ModuleDeclaration: {Annotation} [open] module Identifier {. Identifier} { {ModuleDirective} }

This is not about Automatic-Module-Name part, but based on this module declaration, the module name must be a series of Java identifier concatenated with '.'. In this "graphql-java-extended-scalars" case, hyphens cannot be a part of valid Java identifier, it's not a valid identifier.

It seems that "Automatic-Module-Name" is set since c885c60.

[draftcode]

A point of input: graphql-java uses "com.graphqljava" (https://github.com/graphql-java/graphql-java/blob/master/build.gradle#L83), removing hyphens to make it Java identifier.

[sanvert]

The issue is blocking us to use the new version, can you please change the module name?

[dondonz]

Closed by #79