Update 6.8-specific output

testsuite/tests/ghc-regress/ghci.debugger/scripts/break003-6.8.stderr

@@ -4,4 +4,4 @@
       arising from a use of `print' at <interactive>:1:0
     Possible fix: add an instance declaration for (Show (t -> a))
     In the expression: print it
-    In a 'do' expression: print it
+    In a stmt of a 'do' expression: print it

testsuite/tests/ghc-regress/typecheck/should_fail/tcfail168-6.8.stderr

@@ -3,4 +3,4 @@ tcfail168.hs:8:10:
     Couldn't match expected type `(->) Char' against inferred type `IO'
     Probable cause: `putChar' is applied to too many arguments
     In the expression: putChar 'a'
-    In a 'do' expression: putChar 'a'
+    In a stmt of a 'do' expression: putChar 'a'