[ruby/prism] Generate templated sources under main/java-templates

This path avoids the sources getting wiped out during `mvn clean`,
since they are not generated during the maven build.

This patch also moves the generated WASM build under src/main/wasm
since it is really a source file and not a test file. It will not
be included in the built artifact.

ruby/prism@08dba29eb5

Author: headius

prism/templates/template.rb

@@ -690,9 +690,9 @@ def locals
       "javascript/src/deserialize.js",
       "javascript/src/nodes.js",
       "javascript/src/visitor.js",
-      "java/api/target/generated-sources/java/org/ruby_lang/prism/Loader.java",
-      "java/api/target/generated-sources/java/org/ruby_lang/prism/Nodes.java",
-      "java/api/target/generated-sources/java/org/ruby_lang/prism/AbstractNodeVisitor.java",
+      "java/api/src/main/java-templates/org/ruby_lang/prism/Loader.java",
+      "java/api/src/main/java-templates/org/ruby_lang/prism/Nodes.java",
+      "java/api/src/main/java-templates/org/ruby_lang/prism/AbstractNodeVisitor.java",
       "lib/prism/compiler.rb",
       "lib/prism/dispatcher.rb",
       "lib/prism/dot_visitor.rb",