test(deployment): add revisionHistoryLimit tests and deployment notes

Add helm-unittest tests for revisionHistoryLimit:
- Default value (3) verification
- Custom values support (0, 1, 5, 100)
- Ability to disable revision history

Add NOTES.txt with revisionHistoryLimit information:
- Show configured revision history limit
- Warning when disabled (0)
- Note for minimal history (1)
- Rollback command example for normal values

This parameter controls how many old ReplicaSets are retained
for rollback purposes, reducing etcd storage usage.

Co-Authored-By: Claude <noreply@anthropic.com>
Signed-off-by: Aleksei Sviridkin <f@lex.la>

charts/jellyfin/tests/revision_history_test.yaml

@@ -0,0 +1,41 @@
+suite: test revision history limit
+templates:
+  - deployment.yaml
+tests:
+  - it: should set revisionHistoryLimit to 3 by default
+    asserts:
+      - equal:
+          path: spec.revisionHistoryLimit
+          value: 3
+
+  - it: should allow custom revisionHistoryLimit
+    set:
+      revisionHistoryLimit: 5
+    asserts:
+      - equal:
+          path: spec.revisionHistoryLimit
+          value: 5
+
+  - it: should allow revisionHistoryLimit of 0
+    set:
+      revisionHistoryLimit: 0
+    asserts:
+      - equal:
+          path: spec.revisionHistoryLimit
+          value: 0
+
+  - it: should allow revisionHistoryLimit of 1
+    set:
+      revisionHistoryLimit: 1
+    asserts:
+      - equal:
+          path: spec.revisionHistoryLimit
+          value: 1
+
+  - it: should allow large revisionHistoryLimit
+    set:
+      revisionHistoryLimit: 100
+    asserts:
+      - equal:
+          path: spec.revisionHistoryLimit
+          value: 100