Upgrade to PSSA 1.21.0

[bergmeister]

PR Summary

Expose new setting avoidSemicolonsAsLineTerminators related to new AvoidSemicolonsAsLineTerminators rule in PSSA 1.21.0. Requires this PSES PR first: https://github.com/PowerShell/PowerShellEditorServices/pull/1916

PR Checklist

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