Add support for s390x on UBI

[lucacome]

NGINX now builds for s390x for CentOS/RHEL so now we can too.

[codecov-commenter]

Codecov Report

Merging #2363 (a0073eb) into master (7a702f8) will increase coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2363      +/-   ##
==========================================
+ Coverage   53.66%   53.70%   +0.04%     
==========================================
  Files          48       48              
  Lines       14201    14201              
==========================================
+ Hits         7621     7627       +6     
+ Misses       6340     6336       -4     
+ Partials      240      238       -2     

Impacted Files	Coverage Δ
internal/k8s/configuration.go	95.86% <0.00%> (+0.38%)	⬆️
...ternal/k8s/appprotect/app_protect_configuration.go	86.74% <0.00%> (+0.57%)	⬆️

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