remove test-miri from config.toml.example

Author: RalfJung

config.toml.example

@@ -368,10 +368,6 @@
 # When creating source tarballs whether or not to create a source tarball.
 #dist-src = false
 
-# Whether to also run the Miri tests suite when running tests.
-# As a side-effect also generates MIR for all libraries.
-#test-miri = false
-
 # After building or testing extended tools (e.g. clippy and rustfmt), append the
 # result (broken, compiling, testing) into this JSON file.
 #save-toolstates = "/path/to/toolstates.json"