Fix typo "runs-un" in GHA workflows (Case 171395)

Author: mpdude

.github/workflows/dependencies.yml

@@ -15,7 +15,7 @@ env:
 jobs:
     composer-require-checker:
         name: Check missing composer requirements
-        runs-un: ubuntu-22.04
+        runs-on: ubuntu-22.04
         steps:
             -   uses: shivammathur/setup-php@v2
                 with:

.github/workflows/fix-cs-php.yml

@@ -12,7 +12,7 @@ name: Coding Standards
 jobs:
     open-pr-for-cs-violations:
         name: PHP-CS-Fixer
-        runs-un: ubuntu-22.04
+        runs-on: ubuntu-22.04
         if: github.actor != 'dependabot[bot]'
         steps:
             -   name: Checkout code

.github/workflows/tests.yml

@@ -12,7 +12,7 @@ env:
 jobs:
     PHPUnit:
 
-        runs-un: ubuntu-22.04
+        runs-on: ubuntu-22.04
         strategy:
             fail-fast: false
             matrix: