[RHOAIENG-7425]: Update Pipeline Group Labels and Positioning

[jenny-s51]

https://issues.redhat.com/browse/RHOAIENG-7425

Description

Updates expanded group label to pill shape per design feedback. Also updates arrow positioning to keep the group label connected with other nodes so the user understands it is the parent node.

Before

After

How Has This Been Tested?

1. Upload flip_coin_compiled.yml.zip
2. Expand group(s)
3. Verify that label renders as pill shape on upper group boundary

Test Impact

N/A

Request review criteria:

Self checklist (all need to be checked):

• The developer has manually tested the changes and verified that the changes work
• Commits have been squashed into descriptive, self-contained units of work (e.g. 'WIP' and 'Implements feedback' style messages have been removed)
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has added tests or explained why testing cannot be added (unit or cypress tests for related changes)

If you have UI changes:

• Included any necessary screenshots or gifs if it was a UI change.
• Included tags to the UX team if it was a UI/UX change (find relevant UX in the SMEs section).

After the PR is posted & before it merges:

• The developer has tested their solution on a cluster by using the image produced by the PR to main

[jeff-phillips-18]

/lgtm

[DaoDaoNoCode]

/lgtm

[Gkrumbach07]

/approve

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: DaoDaoNoCode, Gkrumbach07, jeff-phillips-18

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