[charts] Use `store.state` over `store.getSnapshot()`

[bernardobelchior]

Related to https://github.com/mui/mui-x/pull/20457/files#r2603725768.

[mui-bot]

Deploy preview: https://deploy-preview-20616--material-ui-x.netlify.app/

Bundle size report

Bundle	Parsed size	Gzip size
@mui/x-data-grid	0B(0.00%)	0B(0.00%)
@mui/x-data-grid-pro	0B(0.00%)	0B(0.00%)
@mui/x-data-grid-premium	0B(0.00%)	0B(0.00%)
@mui/x-charts	▼-32B(-0.01%)	▼-16B(-0.02%)
@mui/x-charts-pro	▼-136B(-0.03%)	▼-32B(-0.02%)
@mui/x-charts-premium	▼-128B(-0.03%)	▼-29B(-0.02%)
@mui/x-date-pickers	0B(0.00%)	0B(0.00%)
@mui/x-date-pickers-pro	0B(0.00%)	0B(0.00%)
@mui/x-tree-view	0B(0.00%)	0B(0.00%)
@mui/x-tree-view-pro	0B(0.00%)	0B(0.00%)

Details of bundle changes

Generated by :no_entry_sign: dangerJS against a59f52a8d1c9a4199fa2fd85b40ee9ccdd65e461

[codspeed-hq[bot]]

CodSpeed Performance Report

Merging #20616 will not alter performance

_{Comparing bernardobelchior:prefer-store-state (a59f52a) with master (06e8498)[^unexpected-base]} [^unexpected-base]: No successful run was found on master (2fec5b6) during the generation of this report, so 06e8498 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report.

Summary

✅ 13 untouched