[feat]: support certificate authentication and add tests

[themanforfree]

Please briefly answer these questions: based on #648

• what problem are you trying to solve? (or if there's no problem, what's the motivation for this change?) support certificate authentication and add tests
• what changes does this pull request make? support certificate authentication and add tests
• are there any non-obvious implications of these changes? (does it break compatibility with previous versions, etc) no

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 74.03315% with 47 lines in your changes are missing coverage. Please review.

Project coverage is 74.69%. Comparing base (6779d42) to head (9ea486b). Report is 14 commits behind head on master.

Files	Patch %	Lines
crates/xline-test-utils/src/lib.rs	86.07%	2 Missing and 9 partials :warning:
crates/xline/src/server/xline_server.rs	69.44%	4 Missing and 7 partials :warning:
crates/utils/src/lib.rs	0.00%	7 Missing and 1 partial :warning:
crates/xline/src/server/kv_server.rs	16.66%	3 Missing and 2 partials :warning:
crates/xline/src/storage/auth_store/store.rs	88.88%	0 Missing and 3 partials :warning:
crates/xline/src/utils/args.rs	0.00%	3 Missing :warning:
crates/xline/src/server/lock_server.rs	0.00%	2 Missing :warning:
crates/xline/src/server/auth_server.rs	0.00%	0 Missing and 1 partial :warning:
crates/xline/src/server/auth_wrapper.rs	0.00%	0 Missing and 1 partial :warning:
crates/xline/src/server/lease_server.rs	0.00%	0 Missing and 1 partial :warning:
... and 1 more

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #652 +/- ## ========================================== + Coverage 74.43% 74.69% +0.26% ========================================== Files 170 171 +1 Lines 24834 25035 +201 Branches 24834 25035 +201 ========================================== + Hits 18485 18701 +216 + Misses 5207 5161 -46 - Partials 1142 1173 +31 ```

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