gh: use shallow clones whenever possible (#2491)

* gh: use shallow clones whenever possible
* gh: reverted submodule checks
* gh: lint: joined linting scripts
* gh: renamed linter workflow
* check python linter output
* gh: reworked linter
* checking c linter
* gh: merged submodule check & lint
* gh: renamed step
* gh: removed redundant `submodules: false`

Co-authored-by: あく <alleteam@gmail.com>

.github/workflows/unit_tests.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v3
         with:
-          fetch-depth: 0
+          fetch-depth: 1
           ref: ${{ github.event.pull_request.head.sha }}
 
       - name: 'Get flipper from device manager (mock)'