Skip date check when release worfklow is manually invoked (#4484)

- **PR Description**

I just tried creating a release manually and hit an error because it
wasn't the first saturday of the month.

- **Please check if the PR fulfills these requirements**

* [ ] Cheatsheets are up-to-date (run `go generate ./...`)
* [ ] Code has been formatted (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#code-formatting))
* [ ] Tests have been added/updated (see
[here](https://github.com/jesseduffield/lazygit/blob/master/pkg/integration/README.md)
for the integration test guide)
* [ ] Text is internationalised (see
[here](https://github.com/jesseduffield/lazygit/blob/master/CONTRIBUTING.md#internationalisation))
* [ ] If a new UserConfig entry was added, make sure it can be
hot-reloaded (see
[here](https://github.com/jesseduffield/lazygit/blob/master/docs/dev/Codebase_Guide.md#using-userconfig))
* [ ] Docs have been updated if necessary
* [ ] You've read through your own file changes for silly mistakes etc

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.github/workflows/release.yml

@@ -27,6 +27,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check for first Saturday of the month
+        if: ${{ github.event_name != 'workflow_dispatch' }}
         run: |
           if (( $(date +%e) > 7 )); then
             echo "This is not the first Saturday of the month"