Bump actions/checkout from 2.4.0 to 3

Bumps [actions/checkout](https://github.com/actions/checkout) from 2.4.0 to 3.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v2.4.0...v3)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/main.yaml

@@ -29,7 +29,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.4.0"
+        uses: "actions/checkout@v3"
 
       - name: "Setup PHP cache environment"
         id: "extcache"
@@ -88,7 +88,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.4.0"
+        uses: "actions/checkout@v3"
 
       - name: "Setup PHP cache environment"
         id: "extcache"
@@ -154,7 +154,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.4.0"
+        uses: "actions/checkout@v3"
 
       - name: "Setup PHP cache environment"
         id: "extcache"
@@ -218,7 +218,7 @@ jobs:
 
     steps:
       - name: "Checkout"
-        uses: "actions/checkout@v2.4.0"
+        uses: "actions/checkout@v3"
 
       - name: "Setup PHP cache environment"
         id: "extcache"