chore(karpor): bump app version to 0.6.4, chart version to 0.7.6 (#117)

This PR updates the Karpor Helm chart with the following changes:
- Bump the `appVersion` to `0.6.4`
- Bump the `version` to `0.7.6`

These updates ensure that the chart reflects the latest Karpor release.

**Note**: This PR was automatically generated by the
**karpor-chart-updater[bot]**.

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: elliotxx

charts/karpor/Chart.yaml

@@ -1,8 +1,8 @@
 apiVersion: v2
 name: karpor
-version: 0.7.5
+version: 0.7.6
 type: application
-appVersion: 0.6.3
+appVersion: 0.6.4
 description: A modern kubernetes visualization tool (Karpor).
 home: https://github.com/KusionStack/karpor
 icon: https://kusionstack.io/karpor/assets/logo/logo.svg