Added task to patch Lucene.Net.Expressions.csproj with a conditional expression so it can be overridden from the command line

Author: NightOwl888

.github/workflows/Lucene-Net-Performance-Regression.yml

@@ -126,6 +126,46 @@ jobs:
 
           Add-Content $env:GITHUB_OUTPUT "antlr4JarPath=$antlrJar"
 
+      - name: Patch Antlr4ToolPath condition in Lucene.Net.Expressions.csproj
+        shell: pwsh
+        run: |
+          $projFile = "src/Lucene.Net.Expressions/Lucene.Net.Expressions.csproj"
+          if (-not (Test-Path $projFile)) {
+              Write-Warning "Project file not found: $projFile"
+              exit 0
+          }
+
+          [xml]$xml = Get-Content $projFile
+          $nodes = $xml.SelectNodes("//Antlr4ToolPath")
+          if ($nodes.Count -eq 0) {
+              Write-Host "No Antlr4ToolPath element found. No change needed."
+              exit 0
+          }
+
+          $modified = $false
+          foreach ($node in $nodes) {
+              if (-not $node.Attributes["Condition"]) {
+                  $attr = $xml.CreateAttribute("Condition")
+                  $attr.Value = " '$(Antlr4ToolPath)' == '' "
+                  $node.Attributes.Append($attr) | Out-Null
+                  $modified = $true
+                  Write-Host "Added missing Condition attribute to Antlr4ToolPath."
+              }
+          }
+
+          if ($modified) {
+              $utf8NoBom = New-Object System.Text.UTF8Encoding $false
+              $writer = [System.IO.StreamWriter]::new($projFile, $false, $utf8NoBom)
+              try {
+                  $xml.Save($writer)
+              } finally {
+                  $writer.Close()
+              }
+              Write-Host "Patched $projFile successfully."
+          } else {
+              Write-Host "Condition already present. No changes made."
+          }
+
       - name: Restore
         run: dotnet restore