Merge branch 'release/1.2.0'

Change script version

Change copyright date

Fix minor typos and format README.md

Fix double newline

Add support for macOS Tahoe

Improve check for sufficient disk space

Remove unused function

Protect commands against option-like arguments

Add missing check for exit status

Fix wrong exit code

Use '--fixed-strings' option for grep

Remove function call for 'get_os_name'

Prefer using logical operators outside of '[[...]]'

Use absolute path for external commands