[github-actions] remove coverage artifacts after uploading (#5778)

This removes artifacts when they are no longer needed, saves storage
space.

.github/workflows/posix.yml

@@ -303,3 +303,13 @@ jobs:
     - name: Upload Coverage
       run: |
         script/test upload_codecov
+
+  delete-coverage-artifacts:
+    needs: upload-coverage
+    if: always()
+    runs-on: ubuntu-20.04
+    steps:
+    - uses: geekyeggo/delete-artifact@1-glob-support
+      with:
+        name: cov-*
+        useGlob: true

.github/workflows/simulation-1.2.yml

@@ -340,3 +340,13 @@ jobs:
     - name: Upload Coverage
       run: |
         script/test upload_codecov
+
+  delete-coverage-artifacts:
+    needs: upload-coverage
+    if: always()
+    runs-on: ubuntu-20.04
+    steps:
+    - uses: geekyeggo/delete-artifact@1-glob-support
+      with:
+        name: cov-*
+        useGlob: true

.github/workflows/simulation.yml

@@ -518,3 +518,13 @@ jobs:
     - name: Upload Coverage
       run: |
         script/test upload_codecov
+
+  delete-coverage-artifacts:
+    needs: upload-coverage
+    if: always()
+    runs-on: ubuntu-20.04
+    steps:
+    - uses: geekyeggo/delete-artifact@1-glob-support
+      with:
+        name: cov-*
+        useGlob: true

.github/workflows/toranj.yml

@@ -125,3 +125,13 @@ jobs:
     - name: Upload Coverage
       run: |
         script/test upload_codecov
+
+  delete-coverage-artifacts:
+    needs: upload-coverage
+    if: always()
+    runs-on: ubuntu-20.04
+    steps:
+    - uses: geekyeggo/delete-artifact@1-glob-support
+      with:
+        name: cov-*
+        useGlob: true