Linting skips files ending in .theme, .profile and .engine

Migrated issue

Reported by: alexpott

Related to !211 (merged)

Problem/Motivation

The linting is missing 3 file types that in Drupal can contain PHP - .theme .profile and .engine.

Steps to reproduce

Run the linter against a project having a test theme with linting errors in the .theme file.

Proposed resolution

Add the extensions

Remaining tasks

User interface changes

N/a

API changes

N/a

Data model changes

N/a