Add failing test for variables in hovers

Witnesses #2716.

Author: michaelpj

ghcide/test/data/hover/GotoHover.hs

@@ -61,3 +61,6 @@ aa2 = $(id [| True |])
 
 hole :: Int
 hole = _
+
+hole2 :: a -> Maybe a
+hole2 = _

ghcide/test/exe/Main.hs

@@ -4111,6 +4111,7 @@ findDefinitionAndHoverTests = let
   outL45 = Position 49  3  ;  outSig = [ExpectHoverText ["outer", "Bool"], mkR 50 0 50 5]
   innL48 = Position 52  5  ;  innSig = [ExpectHoverText ["inner", "Char"], mkR 49 2 49 7]
   holeL60 = Position 62 7  ;  hleInfo = [ExpectHoverText ["_ ::"]]
+  holeL65 = Position 65 8  ;  hleInfo2 = [ExpectHoverText ["_ :: a -> Maybe a"]]
   cccL17 = Position 17 16  ;  docLink = [ExpectHoverText ["[Documentation](file:///"]]
   imported = Position 56 13 ; importedSig = getDocUri "Foo.hs" >>= \foo -> return [ExpectHoverText ["foo", "Foo", "Haddock"], mkL foo 5 0 5 3]
   reexported = Position 55 14 ; reexportedSig = getDocUri "Bar.hs" >>= \bar -> return [ExpectHoverText ["Bar", "Bar", "Haddock"], mkL bar 3 0 3 14]
@@ -4165,6 +4166,11 @@ findDefinitionAndHoverTests = let
   , test  no     yes    outL45     outSig        "top-level signature              #767"
   , test  broken broken innL48     innSig        "inner     signature              #767"
   , test  no     yes    holeL60    hleInfo       "hole without internal name       #831"
+  , if ghcVersion >= GHC92 then
+        -- Broken on GHC 9.2 and above due to printing of uniques
+        test  no     yes    holeL65    []        "hole with variable"
+    else
+        test  no     yes    holeL65    hleInfo2  "hole with variable"
   , test  no     skip   cccL17     docLink       "Haddock html links"
   , testM yes    yes    imported   importedSig   "Imported symbol"
   , testM yes    yes    reexported reexportedSig "Imported symbol (reexported)"