Update references to the previous team name

[sourcegraph-wk]

This batch changes references to the former team name Client Platform to now reference Frontend Frameworks Architecture.

replace "Client Platform" "Frontend Frameworks Architecture"

QA steps:

CI passing should be sufficient as these changes are documentation changes.

_Created by Sourcegraph batch change Workiva/Update_PR_Template_Team_Names_FEA._

[aviary2-wf]

Security Insights

No security relevant content was detected by automated scans.

Action Items

• Review PR for security impact; comment "security review required" if needed or unsure

• Verify aviary.yaml coverage of security relevant code

  Questions or Comments? Reach out on Slack: #support-infosec.

[robbecker-wf]

QA+1 CI passes

[robbecker-wf]

@Workiva/release-management-p