Add apiUri parameter for github enterprise example case

[solvingj]

Add apiUri parameter for github enterprise example case.

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[codecov]

Codecov Report

Merging #1397 into master will decrease coverage by 0.02%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master    #1397      +/-   ##
============================================
- Coverage     79.29%   79.27%   -0.03%     
  Complexity      790      790              
============================================
  Files            66       66              
  Lines          2314     2311       -3     
  Branches        324      321       -3     
============================================
- Hits           1835     1832       -3     
  Misses          378      378              
  Partials        101      101              

Impacted Files	Coverage Δ	Complexity Δ
...ava/io/jenkins/plugins/casc/TokenReloadAction.java	95.00% <0.00%> (-0.24%)	11.00% <0.00%> (ø%)
...java/io/jenkins/plugins/casc/BaseConfigurator.java	85.27% <0.00%> (-0.15%)	70.00% <0.00%> (ø%)