Prepared queries for mod_offline - rebased

[arcusfelis]

This PR addresses #

Proposed changes include:

• describe the functionality changes
• describe new or updated tests
• describe changes to the documentation

[codecov]

Codecov Report

Merging #3040 (64f4d65) into mu-prepared-queries3 (c3ff8c8) will increase coverage by 0.02%.
The diff coverage is 96.66%.

@@                   Coverage Diff                    @@
##           mu-prepared-queries3    #3040      +/-   ##
========================================================
+ Coverage                 78.48%   78.50%   +0.02%     
========================================================
  Files                       378      378              
  Lines                     31130    31109      -21     
========================================================
- Hits                      24431    24423       -8     
+ Misses                     6699     6686      -13     

Impacted Files	Coverage Δ
src/rdbms/rdbms_queries_mssql.erl	100.00% <ø> (+33.33%)	⬆️
src/offline/mod_offline_rdbms.erl	93.84% <96.55%> (+10.02%)	⬆️
src/rdbms/rdbms_queries.erl	79.62% <100.00%> (-2.63%)	⬇️
src/elasticsearch/mongoose_elasticsearch.erl	76.92% <0.00%> (-7.70%)	⬇️
src/mam/mod_mam_elasticsearch_arch.erl	86.60% <0.00%> (-1.79%)	⬇️
src/cassandra/mongoose_cassandra_worker.erl	72.64% <0.00%> (-0.48%)	⬇️
src/pubsub/mod_pubsub_db_mnesia.erl	92.40% <0.00%> (-0.43%)	⬇️
src/rdbms/mongoose_rdbms.erl	64.58% <0.00%> (-0.42%)	⬇️
src/mod_muc_log.erl	77.72% <0.00%> (ø)
src/mod_muc_room.erl	77.50% <0.00%> (+0.11%)	⬆️
... and 6 more

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[chrzaszcz]

Looks good, only a few comments from me.

[chrzaszcz]

Great!