Add SAML integration

[gtrkiller]

Overview

Add SAML integration using the SAML Integrator charm

Rationale

Simplify the charm's logic and modularize SAML interactions.

Juju Events Changes

Module Changes

Library Changes

Add the SAML

Checklist

• [X] The charm style guide was applied
• [X] The contributing guide was applied
• [X] The changes are compliant with ISD054 - Manging 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 83a808906b4551c746ef1e4b42b5b5f71c1efe36

Name              Stmts   Miss Branch BrPart  Cover   Missing
-------------------------------------------------------------
src/charm.py        338     35     82     11    89%   186, 194-195, 207-219, 384->389, 588-590, 595-596, 607-609, 614-615, 627-629, 634-635, 647-649, 674-676, 718->exit, 728->exit, 758-764, 790->exit, 804-805, 815->exit, 829
src/database.py      30      1      8      1    95%   56
-------------------------------------------------------------
TOTAL               368     36     90     12    89%

Static code analysis report

Run started:2024-03-12 15:46:33.687614

Test results:
    No issues identified.

Code scanned:
    Total lines of code: 2035
    Total lines skipped (#nosec): 3
    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):