iOS: Remove "graded subsection" warning message

Description

Remove the following message completely from the app:
"We recommend that you complete graded exercises like this on the web until it is fully supported on mobile."

Steps to Reproduce

None

Reason for Variance

None

Release Notes

None

Assignee

akivaR

Reporter

jjorgeR

Labels

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URL

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Groups with Read-Only Access

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Actual Points

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Reach

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Impact

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Open edX Discourse Thread

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Platform Map Area (Levels 1 & 2)

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Platform Map Area (Levels 3 & 4)

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Contributor Name

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Blended Project Status Page

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Story Points

0.5

Epic Link

Sprint

None

Fix versions

Priority

CAT-3
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