Update dependency eslint-plugin-flowtype to v3

[renovate]

This PR contains the following updates:

Package	Type	Update	Change	References
eslint-plugin-flowtype	devDependencies	major	^2.50.3 -> ^3.0.0	source

---

Release Notes

gajus/eslint-plugin-flowtype

v3.0.0

Compare Source

Features

• add mixed to no-weak-types (#​362) (5e2bbe9)

BREAKING CHANGES

• mixed is now treated as a weak type by default.

---

Renovate configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Enabled.

♻️ Rebasing: Whenever PR becomes conflicted, or if you modify the PR title to begin with "rebase!".

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

This PR has been generated by Renovate Bot. View repository job log here.

[CLAassistant]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[codecov]

Codecov Report

Merging #323 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #323   +/-   ##
=======================================
  Coverage   93.31%   93.31%           
=======================================
  Files          18       18           
  Lines         434      434           
  Branches       85       85           
=======================================
  Hits          405      405           
  Misses         16       16           
  Partials       13       13

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 9fce9cb...a9dcbb4. Read the comment docs.

[KevinGrandon]

!merge