## Summary
Switch to one matcher w/ all code owner patterns rather than separate
matchers for each code owner pattern. Reduces the run time of
`scripts/check_ftr_code_owners.js` by ~10x.
### Before
```console
▶ node scripts/check_ftr_code_owners.js
info Reading CODEOWNERS file
info Checking ownership for 8653 test files (this will take a while)
info Ownership check complete (took 18.89 s)
succ All test files have a code owner. 🥳
```
#### After
```console
▶ node scripts/check_ftr_code_owners.js
info Checked 8653 test files in 1.59s
succ All test files have a code owner 🥳
```
## Summary
This PR adds a script that determines GitHub code ownership for
functional test files in the Kibana repository.
### Why do we need this?
We want to be able to determine test ownership to allow teams to get a
better overview of their tests (number of tests, number of skipped
tests, number of failures in the last x days, etc).
### What does this PR bring?
This PR is a first step on closing the test ownership gaps. It adds
functionality to determine the GitHub code owner for a given file (in
the `@kbn/code-owners` package) and adds a script that makes use of this
to check if all functional test files have a code owner, reporting the
gaps.
### Future plans
The idea is to include the test ownership information in our ingested
test results, such that we can create dashboards, reports, etc based on
it.
At some point (once all ownership gaps are closed), we might consider
running this check on CI to prevent new test files without owners.
### How to run?
```
node scripts/check_ftr_code_owners.js
```
The script lists the functional test files that are not covered by code
owners and also gives a summary like this:
```
ERROR Found 2592 test files without code owner (checked 7550 test files in 12.73 s)
```
