[DEVOPS-1785] Fix publish Ruby workflow (#628)

## Type of change

<!-- (mark with an `X`) -->

```
- [x] Bug fix
- [ ] New feature development
- [ ] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
- [ ] Build/deploy pipeline (DevOps)
- [ ] Other
```

## Objective

Fix error from ruby release pipeline:
```
Could not find gem 'rspec (~> 3.0)' in locally installed gems.
```

<!--Describe what the purpose of this PR is. For example: what bug
you're fixing or what new feature you're adding-->

## Code changes

<!--Explain the changes you've made to each file or major component.
This should help the reviewer understand your changes-->
<!--Also refer to any related changes or PRs in other repositories-->

- **.github/workflows/publish-ruby.yml:** Replace `gem build` with
`bundle install`

## Before you submit

- Please add **unit tests** where it makes sense to do so

.github/workflows/publish-ruby.yml

@@ -15,7 +15,6 @@ on:
 
 permissions:
   contents: read
-  pages: write
   id-token: write
 
 jobs:
@@ -108,8 +107,8 @@ jobs:
             cp "temp/${platforms[$i]}/${files[$i]}" "languages/ruby/bitwarden_sdk_secrets/lib/${platforms[$i]}/${files[$i]}"
           done
 
-      - name: Build gem
-        run: gem build bitwarden-sdk-secrets.gemspec
+      - name: bundle install
+        run: bundle install
         working-directory: languages/ruby/bitwarden_sdk_secrets
 
       - name: Set remote URL