Add with-ghc.config to reset --with-compiler=ghc

Author: philderbeast

cabal-testsuite/PackageTests/VersionPriority/1-web-constraints-import.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 constraints: hashable ==1.4.2.0
 import: https://www.stackage.org/nightly-2023-12-07/cabal.config
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/1-web-import-constraints.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 import: https://www.stackage.org/nightly-2023-12-07/cabal.config
 constraints: hashable ==1.4.2.0
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/2-web-constraints-import.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 constraints: hashable ==1.4.2.0
 import: stackage-web.config
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/2-web-import-constraints.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 import: stackage-web.config
 constraints: hashable ==1.4.2.0
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/3-web-constraints-import.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 constraints: hashable ==1.4.2.0
 import: hop-web.config
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/3-web-import-constraints.project

@@ -2,3 +2,4 @@ packages: .
 allow-newer: hashable:*
 import: hop-web.config
 constraints: hashable ==1.4.2.0
+import: with-ghc.config

cabal-testsuite/PackageTests/VersionPriority/with-ghc.config

@@ -0,0 +1,7 @@
+-- WARNING: Override the `with-compiler: ghc-x.y.z` of the stackage import, of
+-- https://www.stackage.org/nightly-yyyy-mm-dd/cabal.config. Otherwise tests
+-- will fail with:
+--   -Error: [Cabal-5490]
+--   -Cannot find the program 'ghc'. User-specified path 'ghc-x.y.z' does not
+--    refer to an executable and the program is not on the system path.
+with-compiler: ghc