CI: Remove Strawberry Perl pkg-config

Author: nobu

.github/workflows/mingw.yml

@@ -70,6 +70,19 @@ jobs:
         with:
           ruby-version: '3.2'
 
+      - name: Remove Strawberry Perl pkg-config
+        working-directory:
+        # `pkg-config.bat` included in Strawberry Perl is written in
+        # Perl and doesn't work when another msys2 `perl` precede its
+        # own `perl`.
+        #
+        # ```
+        # Can't find C:\Strawberry\perl\bin\pkg-config.bat on PATH, '.' not in PATH.
+        # ```
+        run: |
+          Get-Command pkg-config.bat | % { ren $_.path ($_.path + "~") }
+        shell: pwsh
+
       - name: Misc system & package info
         working-directory:
         run: |