Remove unused StoredState

[mthaddon]

Applicable spec: N/A

Overview

Remove unused references to StoredState.

Rationale

The charm was no longer using StoredState but still had references to it.

Juju Events Changes

N/A

Module Changes

N/A

Library Changes

N/A

Checklist

• The charm style guide was applied
• The contributing guide was applied
• The changes are compliant with ISD054 - Managing 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 b9f7a89

Name                Stmts   Miss Branch BrPart  Cover   Missing
---------------------------------------------------------------
src/charm.py          529     41    172     31    89%   184-187, 351-352, 552, 583, 589, 634, 669-670, 721-728, 733, 835->840, 839, 841, 846-847, 907, 925, 932, 1022, 1031, 1043, 1064, 1073, 1092, 1096, 1125, 1178, 1310, 1332, 1339->1341, 1384->exit, 1396, 1412, 1449, 1458-1459
src/cos.py             15      0      0      0   100%
src/exceptions.py      17      1      2      1    89%   41
src/types_.py          16      0      0      0   100%
---------------------------------------------------------------
TOTAL                 577     42    174     32    90%

Static code analysis report

Run started:2023-11-24 14:53:30.557710

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 4274
  Total lines skipped (#nosec): 1
  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):