feat: key auth

[3062]

Issues associated with this PR

参考 apisix 的 key-auth 功能，https://apisix.apache.org/zh/docs/apisix/plugins/key-auth/

Solutions

match 部分的结构和代码主要参考 jwtauthn，对 envoy/jwt_authn/v3 进行了一定的删减

UT result

Unit Test is needed if the code is changed, your unit test should cover boundary cases, corner cases, and some exceptional cases. And you need to show the UT result.

Benchmark

If your code involves the processing of every request, you should give the Benchmark Result.

Code Style

• Make sure Goimports has run
• Show Golint result