Update docker image used in github actions

Author: Olivier Dolbeau

.github/workflows/static.yml

@@ -1,22 +1,22 @@
-on: [push, pull_request]
-name: Static analysis
+name: Static code analysis
+
+on: [pull_request]
+
 jobs:
   phpstan:
-    name: PHPStan
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master
-      - name: PHPStan
-        uses: docker://oskarstark/phpstan-ga
+      - name: Run PHPStan
+        uses: docker://jakzal/phpqa:php7.3-alpine
         with:
-          args: analyze --no-progress
+          args: phpstan analyze
 
   php-cs-fixer:
-    name: PHP-CS-Fixer
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master
-      - name: PHP-CS-Fixer
-        uses: docker://oskarstark/php-cs-fixer-ga
+      - name: Run PHP-CS-Fixer
+        uses: docker://jakzal/phpqa:php7.3-alpine
         with:
-          args: --dry-run --diff-format udiff
+            args: php-cs-fixer fix --dry-run --diff-format udiff -vvv