Force fetch tags

Working around this:

```
From https://github.com/cloudflare/ebpf_exporter
 * [new branch]      master     -> origin/master
 * [new tag]         v1.0.0     -> v1.0.0
 * [new tag]         v1.1.0     -> v1.1.0
 * [new tag]         v1.2.0     -> v1.2.0
 * [new tag]         v1.2.1     -> v1.2.1
 * [new tag]         v1.2.2     -> v1.2.2
 * [new tag]         v1.2.3     -> v1.2.3
 * [new tag]         v1.2.4     -> v1.2.4
 ! [rejected]        v1.2.5     -> v1.2.5  (would clobber existing tag)
Error: Process completed with exit code 1.
```

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
       # * https://github.com/actions/checkout/issues/206
       - name: Fetch full git history
         run: |
-          git fetch --prune --unshallow --tags
+          git fetch --prune --unshallow --tags --force
 
       - name: Build BCC and ebpf_exporter
         run: |
@@ -54,7 +54,7 @@ jobs:
       # * https://github.com/actions/checkout/issues/206
       - name: Fetch full git history
         run: |
-          git fetch --prune --unshallow --tags
+          git fetch --prune --unshallow --tags --force
 
       - name: Build BCC and ebpf_exporter
         run: |