chore: change controller's deploy strategy to RollingUpdate due to leader election

[yu-croco]

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this is a chore.
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---

background

Though there was a constraint to use deployment strategy Recreate due to race condition #38, now it seems we don't have to care about deployment strategy as below.

https://cloud-native.slack.com/archives/C01U781DW2E/p1640199673233000

argo-helm got the PR that let controller's deployment strategy configurable, so I wonder we can change the default strategy as RollingUpdate. 🙋

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

Go Published Test Results

2 097 tests   2 097 ✅  2m 49s ⏱️
  118 suites      0 💤
    1 files        0 ❌

Results for commit 0406ff8.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (723f7a9) 81.79% compared to head (0406ff8) 81.77%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3334      +/-   ##
==========================================
- Coverage   81.79%   81.77%   -0.02%     
==========================================
  Files         135      135              
  Lines       20649    20649              
==========================================
- Hits        16889    16886       -3     
- Misses       2885     2888       +3     
  Partials      875      875              

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[github-actions]

E2E Tests Published Test Results

  4 files    4 suites   3h 29m 15s ⏱️
106 tests  98 ✅  6 💤  2 ❌
438 runs  400 ✅ 24 💤 14 ❌

For more details on these failures, see this check.

Results for commit 0406ff8.