Update how-to documentation

[erinecon]

Overview

Edits to four of the how-to guides

Rationale

Improve the formatting, remove passive voice, other general edits

Juju Events Changes

None

Module Changes

None

Library Changes

None

Checklist

• [X] The charm style guide was applied
• [X] The contributing guide was applied
• [X] The changes are compliant with ISD054 - Managing Charm Complexity
• [X] The documentation is generated using src-docs
• [X] The documentation for charmhub is updated
• [X] The PR is tagged with appropriate label (urgent, trivial, complex)

[github-actions[bot]]

Test coverage for 48a06cd7c0a95fd929648a21ddddd01ad1af6e63

Name                       Stmts   Miss Branch BrPart  Cover   Missing
----------------------------------------------------------------------
src/charm.py                 331      9     80      7    96%   630, 671-672, 763->779, 765->774, 774->779, 787-788, 827, 860->exit, 898-904
src/database_observer.py      32      0      4      0   100%
src/s3_observer.py            17      0      0      0   100%
src/saml_observer.py          14      0      0      0   100%
src/smtp_observer.py          15      0      0      0   100%
src/state.py                  73      0     10      0   100%
----------------------------------------------------------------------
TOTAL                        482      9     94      7    97%

Static code analysis report

Run started:2024-08-20 07:07:41.986509

Test results:
    No issues identified.

Code scanned:
    Total lines of code: 2984
    Total lines skipped (#nosec): 2
    Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 0

Run metrics:
    Total issues (by severity):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
    Total issues (by confidence):
        Undefined: 0
        Low: 0
        Medium: 0
        High: 0
Files skipped (0):

[erinecon]

Closing the PR because I did not sign the original commit; will reopen today