Add logs for MTrie checkpoint file creation

[fxamacker]

Updates #1884 #1750 https://github.com/dapperlabs/flow-go/issues/6114

Changes include:

Add more logs during checkpoint file creation. Use INFO instead of DEBUG given the limited frequency and quantity of logs for checkpoint file creation.

These logs can be useful for detecting issues related to checkpoint creation. E.g. the checkpoint duration log can be used by log monitoring programs to alert us if it exceeds a threshold.

[codecov-commenter]

Codecov Report

Merging #1894 (e7de291) into master (244c6f1) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1894   +/-   ##
=======================================
  Coverage   58.18%   58.18%           
=======================================
  Files         580      580           
  Lines       34474    34479    +5     
=======================================
+ Hits        20058    20061    +3     
- Misses      11805    11806    +1     
- Partials     2611     2612    +1     

Flag	Coverage Δ
unittests	58.18% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
ledger/complete/wal/checkpointer.go	63.73% <100.00%> (+0.37%)	⬆️
ledger/complete/wal/compactor.go	71.21% <100.00%> (+1.37%)	⬆️
ledger/complete/wal/wal.go	54.83% <100.00%> (ø)
...le/state_synchronization/execution_data_service.go	88.11% <0.00%> (-1.40%)	⬇️
admin/command_runner.go	79.20% <0.00%> (ø)
engine/collection/synchronization/engine.go	67.93% <0.00%> (ø)

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