Fixes dropdowns not working in Pipelines pages

What does this MR do?

gl-button does not work with dropdowns, it does not have in consideration the target. We need to go back to using regular buttons.

We can't do:

<gl button  data-toggle="dropdown"></gl-button>
<ul class="dropdown"> ....

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/56071 Closes #55893 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• Security reports checked/validated by reviewer