ci: migrate MyPy coverage from Codecov to Coveralls

Move type coverage reporting to Coveralls per aio-libs/multidict#1231.
Updates workflows to use coverallsapp/github-action, removes codecov-token
secret, and drops typing config from .codecov.yml.

Author: aiolibsbot

.codecov.yml

@@ -2,7 +2,7 @@
 
 codecov:
   notify:
-    after_n_builds: 20  # The number of test matrix+lint jobs uploading coverage
+    after_n_builds: 19  # The number of test matrix+lint jobs uploading coverage
     wait_for_ci: false
 
   require_ci_to_pass: false
@@ -40,9 +40,5 @@ coverage:
         paths:
         - tests/
         target: 100%
-      typing:
-        flags:
-        - MyPy
-        target: 100%
 
 ...

.github/workflows/ci-cd.yml

@@ -123,8 +123,6 @@ jobs:
 
   lint:
     uses: ./.github/workflows/reusable-linters.yml
-    secrets:
-      codecov-token: ${{ secrets.CODECOV_TOKEN }}
 
   build-wheels-for-tested-arches:
     name: >-  # ${{ '' } is a hack to nest jobs under the same sidebar category

.github/workflows/reusable-linters.yml

@@ -4,10 +4,6 @@ name: Linters
 
 on:
   workflow_call:
-    secrets:
-      codecov-token:
-        description: Mandatory token for uploading to Codecov
-        required: true
 
 env:
   COLOR: >-  # Supposedly, pytest or coveragepy use this
@@ -66,16 +62,16 @@ jobs:
     - name: Run linters
       run: |
         make lint
-    - name: Send coverage data to Codecov
-      uses: codecov/codecov-action@v6
+    - name: Send coverage data to Coveralls
+      uses: coverallsapp/github-action@v2
       with:
-        token: ${{ secrets.codecov-token }}
+        debug: ${{ runner.debug == '1' && true || false }}
+        fail-on-error: ${{ runner.debug == '1' && false || true }}
         files: >-
           .tox/.tmp/.mypy/python-3.11/cobertura.xml
-        flags: >-
-          CI-GHA,
-          MyPy
-        fail_ci_if_error: true
+        flag-name: MyPy
+        format: cobertura
+        measure: ${{ runner.debug == '1' && true || false }}
     - name: Install spell checker
       run: |
         pip install -r requirements/doc.txt

CHANGES/756.contrib.rst

@@ -0,0 +1,6 @@
+The type preciseness coverage report generated by `MyPy
+<https://mypy-lang.org>`__ is now uploaded to `Coveralls
+<https://coveralls.io/github/aio-libs/frozenlist>`__ and
+will not be included in the `Codecov views
+<https://app.codecov.io/gh/aio-libs/frozenlist>`__ going forward
+-- by :user:`webknjaz`.