Update docs

[erinecon]

Overview

Smaller documentation changes that are specific to the Discourse charm

Rationale

• Index page: Fixed outdated link
• Tutorial: Reformatted one sentence as a note; split up the first block of commands into smaller steps to improve readability (especially for novice users)
• How-to guides: Capitalising non-code references to Juju and Discourse; updated an outdated link; some small grammar changes

Juju Events Changes

None

Module Changes

None

Library Changes

None

Checklist

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

[github-actions]

Test coverage for bb80b5b

Name              Stmts   Miss Branch BrPart  Cover   Missing
-------------------------------------------------------------
src/charm.py        371     41     94     15    88%   184, 192-193, 205, 337->345, 378->383, 395, 577-579, 584-585, 597-599, 604-605, 617-619, 642-644, 686->exit, 696->exit, 745-748, 758-759, 783-784, 796-797, 824-826, 828->833, 830-831, 873-874, 890-891, 901->exit, 915
src/database.py      29      1      8      1    95%   56
-------------------------------------------------------------
TOTAL               400     42    102     16    88%

Static code analysis report

Run started:2024-08-27 14:41:41.409650

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 2337
  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):