[NFC] Add debug and stat counters to assume queries and assume builder

Summary:
Add debug counter and stats counter to assume queries and assume builder
here is the collected stats on a build of check-llvm + check-clang.
  "assume-builder.NumAssumeBuilt": 2720879,
  "assume-builder.NumAssumesMerged": 761396,
  "assume-builder.NumAssumesRemoved": 1576212,
  "assume-builder.NumBundlesInAssumes": 6518809,
  "assume-queries.NumAssumeQueries": 85566380,
  "assume-queries.NumUsefullAssumeQueries": 2727360,
the NumUsefullAssumeQueries stat is actually pessimistic because in a few places queries
ask to keep providing information to try to get better information. and this isn't counted
as a usefull query evem tho it can be usefull

Reviewers: jdoerfert

Reviewed By: jdoerfert

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83506