chore(deps): bump shivammathur/setup-php from 2.26.0 to 2.28.0

Bumps [shivammathur/setup-php](https://github.com/shivammathur/setup-php) from 2.26.0 to 2.28.0.
- [Release notes](https://github.com/shivammathur/setup-php/releases)
- [Commits](shivammathur/setup-php@2.26.0...2.28.0)

---
updated-dependencies:
- dependency-name: shivammathur/setup-php
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/continuous-integration.yml

@@ -31,7 +31,7 @@ jobs:
         uses: "actions/[email protected]"
 
       - name: "Install PHP"
-        uses: "shivammathur/setup-php@2.26.0"
+        uses: "shivammathur/setup-php@2.28.0"
         with:
           php-version: "latest"
           coverage: "none"
@@ -54,7 +54,7 @@ jobs:
         uses: "actions/[email protected]"
 
       - name: "Install PHP"
-        uses: "shivammathur/setup-php@2.26.0"
+        uses: "shivammathur/setup-php@2.28.0"
         with:
           php-version: "latest"
           coverage: "none"
@@ -81,7 +81,7 @@ jobs:
         uses: "actions/[email protected]"
 
       - name: "Install PHP"
-        uses: "shivammathur/setup-php@2.26.0"
+        uses: "shivammathur/setup-php@2.28.0"
         with:
           php-version: "latest"
           coverage: "none"
@@ -107,7 +107,7 @@ jobs:
         uses: "actions/[email protected]"
 
       - name: "Install PHP"
-        uses: "shivammathur/setup-php@2.26.0"
+        uses: "shivammathur/setup-php@2.28.0"
         with:
           php-version: "latest"
           coverage: "pcov"
@@ -141,7 +141,7 @@ jobs:
         uses: "actions/[email protected]"
 
       - name: "Install PHP"
-        uses: "shivammathur/setup-php@2.26.0"
+        uses: "shivammathur/setup-php@2.28.0"
         with:
           php-version: "${{ matrix.php }}"
           coverage: "none"