Skip print026 in the 6.8 branch

It fails for me, but not consistently - possibly only with a validate
build. Seems plausible that the problem is something like library build
flags.

-l = Data.Sequence.Seq (Data.Sequence.Deep 3
-                                          (Data.Sequence.One (Data.Sequence.Elem 'a')) Data.Sequence.Empty
-                                          (Data.Sequence.Two (Data.Sequence.Elem 'b') (Data.Sequence.Elem 'c')))
+l = <Data.Sequence.Deep> (<Data.Sequence.One> 'a') <Data.Sequence.Empty>
+                         (<Data.Sequence.Two> 'b' 'c')

testsuite/tests/ghc-regress/ghci.debugger/scripts/all.T

@@ -24,7 +24,7 @@ test('print022', if_compiler_lt('ghc','6.9', skip), ghci_script, ['print022.scri
 test('print023', normal, ghci_script, ['print023.script'])
 test('print024', normal, ghci_script, ['print024.script'])
 test('print025', normal, ghci_script, ['print025.script'])
-test('print026', normal, ghci_script, ['print026.script'])
+test('print026', if_compiler_lt('ghc','6.9', skip), ghci_script, ['print026.script'])
 test('print027', normal, ghci_script, ['print027.script'])
 test('print028', if_compiler_lt('ghc','6.9', namebase('print028-6.8')), ghci_script, ['print028.script'])
 test('print029', expect_broken(1995), ghci_script, ['print029.script'])