Typo correction in Tags doc

What does this MR do?

I believe there was a small typo in the description of Protected Tags in the docs. Removed the word "as" from Protected tags will prevent anyone from updating or deleting the tag, as and will prevent creation of matching tags based on the permissions you have selected. By default, anyone without Maintainer permission will be prevented from creating tags.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

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• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team