[BUG] [Discover] Missing field in index pattern throws whole page error

[ashwin-pc]

Describe the bug

A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Create an index patter using the saved object api for an index that does not yet exist:

curl -v -X POST  http://localhost:5601/api/saved_objects/index-pattern/ \
-H "osd-xsrf: true" \
-H "content-type: application/json" \
-d '{ "attributes": { "title": "abc*","timeFieldName": "@timestamp" } }'

2. Go to discover and select the index pattern as a datasource
3. See the screenshot below

Expected behavior

An error popup describing the error, but the rest of the page continues to function

OpenSearch Version
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Dashboards Version
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Plugins

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Screenshots

Host/Environment (please complete the following information):

• OS: [e.g. iOS]
• Browser and version [e.g. 22]

Additional context

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