bitmap_count draft impl

[kazantsev-maksim]

Which issue does this PR close?

Rationale for this change

What changes are included in this PR?

How are these changes tested?

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.43%. Comparing base (f09f8af) to head (bc710ab).
⚠️ Report is 568 commits behind head on main.

Files with missing lines	Patch %	Lines
.../scala/org/apache/comet/serde/QueryPlanSerde.scala	0.00%	7 Missing and 1 partial ⚠️
...rc/main/scala/org/apache/comet/serde/bitmaps.scala	0.00%	4 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2518      +/-   ##
============================================
+ Coverage     56.12%   58.43%   +2.30%     
- Complexity      976     1437     +461     
============================================
  Files           119      147      +28     
  Lines         11743    13562    +1819     
  Branches       2251     2361     +110     
============================================
+ Hits           6591     7925    +1334     
- Misses         4012     4402     +390     
- Partials       1140     1235      +95     

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