Group parser tests for concise methods
Fix bug in parsing of concise methods

When the ES6 concise method syntax is used to declare a method, no new
entry is created in the local environment record. Because of this, the
method name should *not* be interpreted as a local variable, and
declaring a variable of that name should raise no warnings.

Resolves gh-2022
Merge pull request #2026 from jugglinmike/2022-concise-method-names

Fix bug in parsing of concise method names