$FilePath = "$env:SystemRoot/WindowsUpdate.log"
$ContentsWithLinebreaks = (Get-Content $FilePath) -join "`r`n"

$FilePath = "$env:SystemRoot/WindowsUpdate.log"
$ContentsWithLinebreaks = (Get-Content $FilePath) -join "`r`n"
$ContentsWithLinebreaks2 = Get-Content $FilePath -Raw
$ContentsWithLinebreaks -eq $ContentsWithLinebreaks2

PS> $ContentsWithLinebreaks -eq $ContentsWithLinebreaks2.TrimEnd("`r`n")
True