Fix typos

[lfrancke]

Description

Fix typos using typos
I had to fix two things in the README file to make markdownlint happy.
There is actually a typo in a parameter... I hope it doesn't break anything :)

Definition of Done Checklist

• Not all of these items are applicable to all PRs, the author should update this template to only leave the boxes in that are relevant
• Please make sure all these things are done and tick the boxes

Author

• Changes are OpenShift compatible
• CRD changes approved
• CRD documentation for all fields, following the style guide.
• Integration tests passed (for non trivial changes)
• Changes need to be "offline" compatible

Reviewer

• Code contains useful comments
• Code contains useful logging statements
• (Integration-)Test cases added
• Documentation added or updated. Follows the style guide.
• Changelog updated
• Cargo.toml only contains references to git tags (not specific commits or branches)

Acceptance

• Feature Tracker has been updated
• Proper release label has been added

[dervoeti]

I hope it doesn't break anything

Should not, Rust doesn't have named function parameters and the struct field is private. But I grepped for subject_alterative in the operators, just to be safe, looks good.