Fix typos in the codebase. 99% are comments.

[mircobabini]

All Submissions:

• Have you followed the Contributing guideline?
• Does your code follow the WordPress' coding standards?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changes proposed in this Pull Request:

Used https://github.com/crate-ci/typos with the following _typos.toml.
99% are comments. Just one variable rename and one fix in mimetype lib from 2022.

[default]
extend-ignore-identifiers-re = [
    "[A-Z]{2}",
    'dorder',
    'optin',
]

[files]
extend-exclude = [
    "*.sql",
    "tests/*",
    "js/jsapi.js",
    "js/corechart.js",
    "includes/lib/*",
    "languages/*.po*",
    "languages/email/*",
    "languages/pages/*",
    "services/twocheckout*",
    "readme.txt",
    "CHANGELOG.txt",
]