Adjust CI to split tests into 6 groups (#60198)

.github/workflows/ci.yaml

@@ -670,7 +670,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        group: [1, 2, 3, 4]
+        group: [1, 2, 3, 4, 5, 6]
         python-version: [3.8, 3.9]
     name: >-
       Run tests Python ${{ matrix.python-version }} (group ${{ matrix.group }})
@@ -709,7 +709,7 @@ jobs:
             --durations=10 \
             -n auto \
             --dist=loadfile \
-            --test-group-count 4 \
+            --test-group-count 6 \
             --test-group=${{ matrix.group }} \
             --cov homeassistant \
             --cov-report= \