fix(graphql_formatter): panic in block comments with empty line

[vohoanglong0107]

Summary

Fixes #3924
Previously the formatter tried to format block comments by removing the indentation in those comments, but it forgot to take empty lines into account when calculating and subtracting the indent level.

Also allows the formatter to format line with only spaces and tabs

Test Plan

Added a new test containing block comment with empty lines and lines with only white spaces

[codspeed-hq]

CodSpeed Performance Report

Merging #3993 will degrade performances by 35.79%

_{Comparing vohoanglong0107:fix-3924 (7cde444) with main (1a87927)}

Summary

⚡ 1 improvements
❌ 2 regressions
✅ 104 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	vohoanglong0107:fix-3924	Change
❌	big5-added_15586211152145260264.json[uncached]	546.7 µs	851.5 µs	-35.79%
⚡	db_17847247775464589309.json[cached]	13.9 ms	12.7 ms	+9.74%
❌	eucjp_1600564308684076393.json[uncached]	974.1 µs	1,249.5 µs	-22.04%

[Conaclos]

LGTM. Could you add a changelog entry?