Fix misc spelling in MariaDB Server repository

[ottok]

• [ ] The Jira issue number for this PR is: MDEV-______

Description

This is a combined patch of various spelling fixes.

• Fix misc typos in MariaDB Server

• Fix spelling of 'allows one to'

  Fix the following Lintian nags introduced in commit c8d040938a7ebe10e62506a726702c5990ef4dda:

  I: mariadb-backup: spelling-error-in-binary "allows to" "allows one to" [usr/bin/mariadb-backup] I: mariadb-server-core: spelling-error-in-binary "allows to" "allows one to" [usr/sbin/mariadbd] I: mariadb-test: spelling-error-in-binary "allows to" "allows one to" [usr/bin/mariadb-client-test-embedded] I: mariadb-test: spelling-error-in-binary "allows to" "allows one to" [usr/bin/mariadb-test-embedded] I: mariadb-test: spelling-error-in-binary "allows to" "allows one to" [usr/bin/test-connect-t]

• Fix typo: Enrypt->Encrypt

Release Notes

N/A

How can this PR be tested?

MTR did not regress. This has been in this exact form in Debian since Feb 2025, and much longer in partial forms (https://salsa.debian.org/mariadb-team/mariadb-server/-/commit/222e8686363f9b53894c328878dcf7d4ba402bca). No Debian user or QA system has reported any regressions.

Basing the PR against the correct MariaDB version

• [x] This is a new feature or a refactoring, and the PR is based against the main branch.
• [] This is a bug fix, and the PR is based against the earliest maintained branch in which the bug can be reproduced.

PR quality check

• [x] I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• [x] For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.