Refactor server type to include SSLCert

[hnrytrn]

What this PR does / why we need it:

This PR refactors the server type to include the ingress.SSLCert field. This gives us access to the certificate, which will be used to support serving SSL certificates dynamically in dynamic-configuration mode.

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[aledbf]

@hnrytrn can you sign the CLA please?

[codecov-io]

Codecov Report

Merging #2678 into master will increase coverage by 0.07%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #2678      +/-   ##
==========================================
+ Coverage   40.93%   41.01%   +0.07%     
==========================================
  Files          72       72              
  Lines        5088     5083       -5     
==========================================
+ Hits         2083     2085       +2     
+ Misses       2721     2710      -11     
- Partials      284      288       +4

Impacted Files	Coverage Δ
internal/ingress/controller/metrics.go	27.27% <0%> (ø)	⬆️
internal/ingress/types_equals.go	13.17% <0%> (+0.84%)	⬆️
internal/ingress/controller/controller.go	2.25% <0%> (ø)	⬆️

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[aledbf]

/lgtm
/approve

[aledbf]

@hnrytrn thanks!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• OWNERS [aledbf]

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