Bump shivammathur/setup-php from 2.15.0 to 2.16.0

Bumps [shivammathur/setup-php](https://github.com/shivammathur/setup-php) from 2.15.0 to 2.16.0.
- [Release notes](https://github.com/shivammathur/setup-php/releases)
- [Commits](shivammathur/setup-php@2.15.0...2.16.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/continuous-integration.yml

@@ -25,7 +25,7 @@ jobs:
         uses: actions/checkout@v2.4.0
 
       - name: "Install PHP with extensions"
-        uses: shivammathur/setup-php@2.15.0
+        uses: shivammathur/setup-php@2.16.0
         with:
           coverage: none
           extensions: "mbstring, json"
@@ -77,7 +77,7 @@ jobs:
         uses: actions/checkout@v2.4.0
 
       - name: "Install PHP with extensions"
-        uses: shivammathur/setup-php@2.15.0
+        uses: shivammathur/setup-php@2.16.0
         with:
           coverage: none
           extensions: "mbstring, json"
@@ -127,7 +127,7 @@ jobs:
         uses: actions/checkout@v2.4.0
 
       - name: "Install PHP with extensions"
-        uses: shivammathur/setup-php@2.15.0
+        uses: shivammathur/setup-php@2.16.0
         with:
           coverage: none
           extensions: "mbstring, json"
@@ -173,7 +173,7 @@ jobs:
         uses: actions/checkout@v2.4.0
 
       - name: "Install PHP with extensions"
-        uses: shivammathur/setup-php@2.15.0
+        uses: shivammathur/setup-php@2.16.0
         with:
           coverage: pcov
           extensions: "mbstring, json"
@@ -213,7 +213,7 @@ jobs:
         uses: actions/checkout@v2.4.0
 
       - name: "Install PHP with extensions"
-        uses: shivammathur/setup-php@2.15.0
+        uses: shivammathur/setup-php@2.16.0
         with:
           coverage: pcov
           extensions: "mbstring"