Minor initiatives tweak: "typically" need to prepare an RFC

Some initiatives may occasionally end with something other than an RFC,
based on guidance from the team. Allow for that possibility in the
process. (This may warrant further expansion.)

Author: joshtriplett

src/initiatives/process/stages/experimental.md

@@ -26,7 +26,7 @@ During this stage, the owner and the liaison should meet on a regular basis. The
 
 ### Exit: RFC approval
 
-To exit the Experimental stage, you need to prepare an RFC on the rust-lang/rfcs repository. This RFC needs to be approved by the lang team. The RFC can include "unresolved questions" to be resolved during the "development" phase.
+To exit the Experimental stage, you typically need to prepare an RFC on the rust-lang/rfcs repository. This RFC needs to be approved by the lang team. The RFC can include "unresolved questions" to be resolved during the "development" phase.
 
 ### Exit: Go inactive