update mima url (#27407)

CONTRIBUTING.md

@@ -217,7 +217,7 @@ e.g. `allCluster`, `allTyped`.
 Binary compatibility rules and guarantees are described in depth in the [Binary Compatibility Rules
 ](http://doc.akka.io/docs/akka/snapshot/common/binary-compatibility-rules.html) section of the documentation.
 
-Akka uses MiMa (which is short for [Lightbend Migration Manager](https://github.com/typesafehub/migration-manager)) to
+Akka uses [MiMa](https://github.com/lightbend/mima) to
 validate binary compatibility of incoming pull requests. If your PR fails due to binary compatibility issues, you may see 
 an error like this:
 

akka-docs/src/main/paradox/common/binary-compatibility-rules.md

@@ -148,8 +148,8 @@ possible, however these markers allow to experiment, gather feedback and stabili
 
 ## Binary Compatibility Checking Toolchain
 
-Akka uses the Lightbend maintained [Migration Manager](https://github.com/typesafehub/migration-manager), 
-called `MiMa` for short, for enforcing binary compatibility is kept where it was promised.
+Akka uses the Lightbend maintained [MiMa](https://github.com/lightbend/mima),
+for enforcing binary compatibility is kept where it was promised.
 
 All Pull Requests must pass MiMa validation (which happens automatically), and if failures are detected,
 manual exception overrides may be put in place if the change happened to be in an Internal API for example.

akka-stream/src/main/mima-filters/2.5.x.backwards.excludes

@@ -67,7 +67,7 @@ ProblemFilters.exclude[DirectMissingMethodProblem]("akka.stream.ActorAttributes#
 
 # #24372 No Future/CompletionStage in StreamRefs
 # no filter because MiMa doesn't check the generic signature
-# https://github.com/lightbend/migration-manager/issues/40
+# https://github.com/lightbend/mima/issues/40
 
 # 26188 remove Timed
 ProblemFilters.exclude[MissingClassProblem]("akka.stream.extra.Timed$TimedFlowContext")