Avoid hardcoding the template folder for Qute

See https://github.com/redhat-developer/quarkus-ls/pull/834#issuecomment-1488897566

In a few spots, we hard code the folder that the templates are expected to be in. However, in Eclipse, Maven, and Gradle projects, you can configure the resources directory to be in a different location. It would be nice if we avoided hardcoding the value so that qute-ls works properly with projects that change the location of the resource folder.

Some features that currently break when you change the location of the resources folder are:

• CodeLens in Java files that reference a type-checked template (see https://quarkus.io/guides/qute-reference#typesafe_templates for an example)
• vscode-quarkus doesn't recognize files in the template folder as Qute templates until a Java file is opened (I'm not sure if this is handled by vscode-quarkus or quarkus-ls)

Start with the linked pull request discussion and trace where qute-ls assumes the template folder location, including the Java-file CodeLens path and template recognition reported for vscode-quarkus. Compare this with configurable resource directories in Eclipse, Maven, and Gradle projects; done means those features work when the resources directory is moved.