Bump Cabal submodule

Cabal @ 6671506b

-Subproject commit 2a3175f886b86697194256f55c9487b7cfb4dc92
+Subproject commit 6671506b488a0fe2079f9059a23510b35514c031

testsuite/tests/cabal/cabal05/cabal05.stderr

-the following packages have broken abi-depends fields:
-    p
-    q
-    r
 
 T.hs:3:1: error:
     Ambiguous module name ‘Conflict’:

utils/check-api-annotations/check-api-annotations.cabal

@@ -24,6 +24,6 @@ Executable check-api-annotations
 
     Build-Depends: base       >= 4   && < 5,
                    containers,
-                   Cabal      >= 2.3 && < 2.4,
+                   Cabal      >= 2.4.0 && < 2.5,
                    directory,
                    ghc

utils/check-ppr/check-ppr.cabal

@@ -25,7 +25,7 @@ Executable check-ppr
     Build-Depends: base       >= 4   && < 5,
                    bytestring,
                    containers,
-                   Cabal      >= 2.3 && < 2.4,
+                   Cabal      >= 2.4 && < 2.5,
                    directory,
                    filepath,
                    ghc

utils/ghc-cabal/ghc-cabal.cabal

@@ -21,7 +21,7 @@ Executable ghc-cabal
 
     Build-Depends: base       >= 3   && < 5,
                    bytestring >= 0.10 && < 0.11,
-                   Cabal      >= 2.3 && < 2.4,
+                   Cabal      >= 2.4 && < 2.5,
                    directory  >= 1.1 && < 1.4,
                    filepath   >= 1.2 && < 1.5
 

utils/ghctags/ghctags.cabal

@@ -18,6 +18,6 @@ Executable ghctags
 
     Build-Depends: base       >= 4   && < 5,
                    containers,
-                   Cabal      >= 2.3 && <2.4,
+                   Cabal      >= 2.4 && <2.5,
                    ghc