fix(releases): Add null checks for ECharts options in drawer

[seer-by-sentry]

This PR addresses the TypeError: Cannot read properties of undefined (reading 'series') occurring in releasesDrawerList.tsx.

Root Cause: The error stemmed from a race condition where echartsInstance.getOption() would return undefined (or series or markLine.data would be unavailable) when the ECharts chart was in a transitional state, such as during loading, unmounting, or re-rendering. This often happened when mouse events (like onMouseOutRelease) were triggered while the chart was not fully initialized or was being disposed.

Solution: Defensive null checks have been added within the createMarkLineUpdater function. Specifically, the code now checks if echartsInstance.getOption() returns a valid options object, and subsequently, if the series and markLine.data properties exist before attempting to access them. This prevents the TypeError by gracefully handling scenarios where the chart's state is not yet ready or is being torn down.

Closes JAVASCRIPT-33FS

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