fix small typos in base dtx files

[mbertucci47]

Fixes a few small typos in the base dtx files.

Internal housekeeping

Status of pull request

• Ready to merge

Checklist of required changes before merge will be approved

• Test file(s) added
• Version and date string updated in changed source files
• Relevant \changes entries in source included
• Relevant changes.txt updated
• Rollback provided (if necessary)?
• ltnewsX.tex (and/or latexchanges.tex) updated

[mbertucci47]

A test failed because I changed occured -> occurred in an error message in ltluatex.dtx. I can revert that change if it's a pain to fix the test files

[muzimuzhi]

@mbertucci47 Running l3build save -eluatex tlb-callbacks-002 in ./base directory should update ./base/testfiles/tlb-callbacks-002.luatex.tlg, the only affected .tlg file.

[mbertucci47]

@muzimuzhi Thanks, done

[FrankMittelbach]

side remark: co-ordinate is the more common spelling in the UK as far as I know and both are "correct", but we might as well drop the hyphen since we lean towards US spelling (well some of us :-))