Jest: Unify `no tests found` message when running MPR

[aaronabramov]

currently, if there are no test found matching a pattern when running jest in Multi project runner mode we get a very noisy output for each separate project. we need to unify it into one single message for all projects.
example:

[rogeliog]

I also find this super noisy

How about something like this?

In /path/to/root
  781 files checked across 8 projects. for more details run with `--verbose`

running with --verbose would give as similar output as today's behavior.

[rogeliog]

Unrelated note: Once displayName gets merged, it might be a good idea to add it to this output

In PROJECT_1 /some/path/to/project
  X files checked.
  testMatch: **/__tests__/**/*.js?(x),**/?(*.)(spec|test).js?(x) - X matches
  testPathIgnorePatterns: /node_modules/ - X matches

In PROJECT_2 /some/path/to/project2
  Y files checked.
  testMatch: **/__tests__/**/*.js?(x),**/?(*.)(spec|test).js?(x) - Y matches
  testPathIgnorePatterns: /node_modules/ - Y matches

[cpojer]

Agree with @rogeliog, both of these suggestions make a lot of sense to me.

[chitchu]

I'd like to work on this. I'll have the PR shortly.

[rogeliog]

Awesome!