Code quality and cleanliness changes according to Lombiq's PowerShell conventions (INFRA-128)

[BenedekFarkas]

Starting from @DAud-IcI's feedback under #5, several code styling patterns in older scripts/modules need to be brought up to par with our conventions, e.g.:

1. HelpMessages should concise and descriptive.
2. Unnecessary parenthesis around the input of throw and Write-Warning/Error commands.
3. Multi-line strings should use the "Binary -join operator" format, see: OSOE-501: Enable further analyzer rules for better code styling control and more in Lombiq.Analyzers.PowerShell GitHub-Actions#179 (comment)
4. Parameter splatting instead of backtick and line breaks. Fixed in OSOE-482: Enforce parameter splatting instead of backtick in Lombiq.Analyzers.PowerShell #10.

Jira issue