Update excalidraw Helm chart values for clarity
Modified the values.yaml file for the excalidraw Helm chart
to enhance clarity and configuration consistency. Specific
changes include setting defaults for undefined values
such as image tag, pod security context, and resources,
ensuring that users can easily identify where to fill in
custom configurations. This update aims to prevent confusion
for users who might overlook required values due to empty
fields, thereby improving the overall user experience and
configuration process.
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