fix: correct help text for update subcommand

Description

Fixes wrong help text for update subcommand introduced in 679a8297442f17d8adc9428aca304c8892d0eee9

Please select relevant options.

[x] Bug fix (non-breaking change which fixes an issue)
[ ] New feature (non-breaking change which adds functionality)
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
[ ] This change requires a documentation update

[ ] My code follows the contribution guidelines of this project
[ ] I have performed a self-review of my own code
[ ] I have commented my code, particularly in hard-to-understand areas
[ ] My changes generate no new warnings
[ ] I formatted the code with cargo fmt
[ ] I checked my code using cargo clippy and reports no warnings
[ ] I have added tests that prove my fix is effective or that my feature works
[ ] I have introduced no new C-bindings
[ ] The changes I've made are Windows, MacOS, UNIX, Linux compatible (or I've handled them using cfg target_os)
[ ] I increased or maintained the code coverage for the project, compared to the previous commit

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