PSScriptAnalyzer fixes by category (#4261)

- Fix PSScriptAnalyzer warnings of type PSAvoidUsingCmdletAliases for 'ForEach-Object' (alias is '%' or 'foreach')
- Fix PSScriptAnalyzer warnings of type PSAvoidUsingCmdletAliases for 'Where-Object' (alias is '?' or 'where')
- Fix PSScriptAnalyzer warnings of type PSAvoidUsingCmdletAliases for 'Select-Object' (alias is 'select')
- Fix PSScriptAnalyzer warnings of type PSPossibleIncorrectComparisonWithNull. Essentially, $null has to be on the left-hand side when using it for comparison.
- A Test in ParameterBinding.Tests.ps1 needed adapting as this test used to rely on the wrong null comparison
- Replace a subset of tests of kind '($object -eq $null) | Should Be $true' with '$object | Should Be $null'

test/powershell/engine/Help/HelpSystem.OnlineHelp.Tests.ps1

@@ -29,7 +29,7 @@
         foreach ($cmdlet in $cmdletList)
         {
             # If the cmdlet is not preset in CoreCLR, skip it.
-            $skipTest = (Get-Command $cmdlet.TopicTitle -ea SilentlyContinue) -eq $null
+            $skipTest = $null -eq (Get-Command $cmdlet.TopicTitle -ea SilentlyContinue)
 
             # TopicTitle - is the cmdlet name in the csv file
             # HelpURI - is the expected help URI in the csv file

test/powershell/engine/Help/UpdatableHelpSystem.Tests.ps1

@@ -265,11 +265,11 @@ function ValidateSaveHelp
         [string]$path
     )
 
-    $compressedFile = GetFiles -fileType "*$extension" -path $path | foreach {Split-Path $_ -Leaf}
+    $compressedFile = GetFiles -fileType "*$extension" -path $path | ForEach-Object {Split-Path $_ -Leaf}
     $expectedCompressedFile = $testCases[$moduleName].CompressedFiles
     $expectedCompressedFile | Should Be $compressedFile
 
-    $helpInfoFile = GetFiles -fileType "*HelpInfo.xml" -path $path | foreach {Split-Path $_ -Leaf}
+    $helpInfoFile = GetFiles -fileType "*HelpInfo.xml" -path $path | ForEach-Object {Split-Path $_ -Leaf}
     $expectedHelpInfoFile = $testCases[$moduleName].HelpInfoFiles
     $expectedHelpInfoFile | Should Be $helpInfoFile
 }