Adding RestActions support Delete Detector API

[saratvemulapalli]

Issue #195 :

Description of changes: Adding RestActions support for Delete Detector API for FGAC

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[codecov]

Codecov Report

Merging #238 into master will increase coverage by 0.45%.
The diff coverage is 60.37%.

@@             Coverage Diff              @@
##             master     #238      +/-   ##
============================================
+ Coverage     72.12%   72.57%   +0.45%     
- Complexity     1295     1328      +33     
============================================
  Files           146      149       +3     
  Lines          6005     6101      +96     
  Branches        469      480      +11     
============================================
+ Hits           4331     4428      +97     
+ Misses         1462     1454       -8     
- Partials        212      219       +7     

Flag	Coverage Δ	Complexity Δ
#cli	78.11% <ø> (ø)	0.00 <ø> (ø)
#plugin	71.94% <60.37%> (+0.51%)	1328.00 <23.00> (+33.00)

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Impacted Files	Coverage Δ	Complexity Δ
...stroforelasticsearch/ad/util/RestHandlerUtils.java	96.96% <0.00%> (-3.04%)	13.00 <0.00> (ø)
...earch/ad/rest/RestDeleteAnomalyDetectorAction.java	53.84% <25.00%> (+37.77%)	4.00 <0.00> (ø)
...ransport/DeleteAnomalyDetectorTransportAction.java	54.21% <54.21%> (ø)	15.00 <15.00> (?)
...stroforelasticsearch/ad/AnomalyDetectorPlugin.java	93.54% <100.00%> (ø)	10.00 <0.00> (ø)
...arch/ad/transport/DeleteAnomalyDetectorAction.java	100.00% <100.00%> (ø)	2.00 <2.00> (?)
...rch/ad/transport/DeleteAnomalyDetectorRequest.java	100.00% <100.00%> (ø)	6.00 <6.00> (?)
...sticsearch/ad/indices/AnomalyDetectionIndices.java	61.59% <0.00%> (-0.73%)	23.00% <0.00%> (-1.00%)
...on/opendistroforelasticsearch/ad/ml/RcfResult.java	100.00% <0.00%> (ø)	14.00% <0.00%> (+2.00%)
...oforelasticsearch/ad/ml/rcf/CombinedRcfResult.java	100.00% <0.00%> (ø)	12.00% <0.00%> (+2.00%)
...relasticsearch/ad/transport/RCFResultResponse.java	100.00% <0.00%> (ø)	8.00% <0.00%> (+1.00%)
... and 6 more