Fixed a typo

Author: ScrapCodes

project/MimaBuild.scala

@@ -32,7 +32,7 @@ object MimaBuild {
       ProblemFilters.exclude[MissingMethodProblem](fullName),
       // Sometimes excluded methods have default arguments and 
       // they are translated into public methods/fields($default$) in generated
-      // bytecode. It is not possible to exhustively list everything.
+      // bytecode. It is not possible to exhaustively list everything.
       // But this should be okay.
       ProblemFilters.exclude[MissingMethodProblem](fullName+"$default$2"),
       ProblemFilters.exclude[MissingMethodProblem](fullName+"$default$1"),