skip codecov upload on Dependabot PRs (#1425)

Dependabot PRs run in a sandboxed environment without access to
repository secrets, so `CODECOV_TOKEN` is unavailable and the codecov
upload fails with:

```
Upload queued for processing failed: {"message":"Token required because branch is protected"}
```

This adds `if: github.actor != 'dependabot[bot]'` to each
`codecov/codecov-action` step so the upload is skipped for Dependabot
PRs. No coverage changes are expected from dependency bumps, so this is
safe.

Automated by
[dependabot-config-bot](https://github.com/shravangoswami-bot/dependabot-config-bot).

Co-authored-by: shravangoswami-bot <shravangoswami-bot@users.noreply.github.com>

Author: shravangoswami-bot

.github/workflows/CI.yml

@@ -76,6 +76,7 @@ jobs:
       - uses: julia-actions/julia-processcoverage@v1
 
       - uses: codecov/codecov-action@v7
+        if: github.actor != 'dependabot[bot]'
         with:
           files: lcov.info
           token: ${{ secrets.CODECOV_TOKEN }}
@@ -101,6 +102,7 @@ jobs:
       - uses: julia-actions/julia-processcoverage@v1
 
       - uses: codecov/codecov-action@v7
+        if: github.actor != 'dependabot[bot]'
         with:
           files: lcov.info
           token: ${{ secrets.CODECOV_TOKEN }}
@@ -126,6 +128,7 @@ jobs:
       - uses: julia-actions/julia-processcoverage@v1
 
       - uses: codecov/codecov-action@v7
+        if: github.actor != 'dependabot[bot]'
         with:
           files: lcov.info
           token: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/Enzyme.yml

@@ -37,6 +37,7 @@ jobs:
       - uses: julia-actions/julia-processcoverage@v1
 
       - uses: codecov/codecov-action@v7
+        if: github.actor != 'dependabot[bot]'
         with:
           files: lcov.info
           token: ${{ secrets.CODECOV_TOKEN }}