v1.2.1: For Armita Geravand

For Armita Geravand
Highlights:

• Update to golang v1.21
• Refactor logic for the appending of subsections
• Fix bugs

thanks @fmartingr @ChengShusss @ALIBRAGIMOV

What's Changed

• fix: misplaced subsection position in toc.ncx by @ChengShusss in #13
• fix: Append subsection to subsection by @Monirzadeh in #18
• fix: ineffectual assignment to parentIndex by @Monirzadeh in #19
• update to golang v1.21 by @Monirzadeh in #21
• deps: add dependabot by @Monirzadeh in #23
• fix: add file extension at the end of filename if not provided by @Monirzadeh in #20
• ci: add codecov support by @fmartingr in #24
• deps: Update Dependencies by @Monirzadeh in #25

New Contributors

• @ChengShusss made their first contribution in #13
• @fmartingr made their first contribution in #24

Full Changelog: v1.2.0...v1.2.1