Mpdf v8.1.6 support

[jakejackson1]

Description

Allows PSR Log v2 or v3 to be used.

Testing instructions

Screenshots

Checklist:

• [ ] I've tested the code.
• [ ] My code is easy to read, follow, and understand
• [ ] My code follows the accessibility standards.
• [ ] My code has proper inline documentation / docblocks.

Additional Comments

[codecov[bot]]

Codecov Report

Merging #1460 (fe0d887) into development (1151ff6) will increase coverage by 17.58%. The diff coverage is n/a.

:exclamation: Current head fe0d887 differs from pull request most recent head 0efc62e. Consider uploading reports for the commit 0efc62e to get more accurate results

@@                Coverage Diff                 @@
##             development    #1460       +/-   ##
==================================================
+ Coverage          75.71%   93.30%   +17.58%     
==================================================
  Files                243       57      -186     
  Lines              12828     1464    -11364     
  Branches             370      370               
==================================================
- Hits                9713     1366     -8347     
+ Misses              3107       90     -3017     
  Partials               8        8               

see 186 files with indirect coverage changes

[jakejackson1]

Merged in https://github.com/GravityPDF/gravity-pdf/pull/1461