chore: elasticsearch -> opensearch

[richardzilincikPantheon]

renaming everywhere

[codecov]

Codecov Report

Merging #784 (779359e) into develop (428063c) will increase coverage by 0.00%.
The diff coverage is 74.16%.

❗ Current head 779359e differs from pull request most recent head d247afe. Consider uploading reports for the commit d247afe to get more accurate results

@@           Coverage Diff            @@
##           develop     #784   +/-   ##
========================================
  Coverage    77.74%   77.74%           
========================================
  Files          110      110           
  Lines        11393    11392    -1     
========================================
  Hits          8857     8857           
+ Misses        2536     2535    -1     

Impacted Files	Coverage Δ
api/views/redis_search.py	69.68% <ø> (ø)
opensearch_indexing/__init__.py	100.00% <ø> (ø)
opensearch_indexing/models/keywords_names.py	100.00% <ø> (ø)
opensearch_indexing/pyang_plugin/json_tree.py	59.91% <ø> (ø)
utility/script_config_dict.py	100.00% <ø> (ø)
api/views/yang_search/yang_search.py	14.31% <12.50%> (+0.05%)	⬆️
api/views/health_check.py	21.22% <22.22%> (ø)
utility/opensearch_util.py	19.13% <33.33%> (ø)
api/views/yang_search/opensearch_query.py	17.00% <41.66%> (ø)
opensearch_indexing/opensearch_manager.py	70.91% <80.51%> (ø)
... and 12 more