KEP: Remove static SSL configuration mode

[aledbf]

What this PR does / why we need it:

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

[codecov-io]

Codecov Report

Merging #4351 into master will increase coverage by 2.52%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4351      +/-   ##
==========================================
+ Coverage   58.47%   60.99%   +2.52%     
==========================================
  Files          87       89       +2     
  Lines        6528     7953    +1425     
==========================================
+ Hits         3817     4851    +1034     
- Misses       2282     2601     +319     
- Partials      429      501      +72

Impacted Files	Coverage Δ
internal/ingress/sslcert.go	25% <0%> (-25%)	⬇️
cmd/nginx/flags.go	83.75% <0%> (-5.66%)	⬇️
internal/ingress/annotations/annotations.go	78.4% <0%> (-2.48%)	⬇️
internal/ingress/controller/config/config.go	97.91% <0%> (-0.66%)	⬇️
internal/ingress/types.go	0% <0%> (ø)	⬆️
internal/ingress/annotations/mirror/main.go	100% <0%> (ø)
internal/ingress/annotations/fastcgi/main.go	100% <0%> (ø)
internal/ingress/controller/template/template.go	84.54% <0%> (+0.61%)	⬆️
internal/ingress/metric/collectors/process.go	90.42% <0%> (+2.12%)	⬆️
internal/ingress/controller/store/backend_ssl.go	58.73% <0%> (+2.15%)	⬆️
... and 9 more

---

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 e1f062d...374045d. Read the comment docs.

[ElvinEfendi]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aledbf, ElvinEfendi

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [ElvinEfendi,aledbf]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment