Remove a note in release-5.0.5.md

[qqqdan]

delele a wrong info , the grafaba upgrade is not in 5.0.5, and it will be in 5.0.6

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• master (the latest development version)
• v5.3 (TiDB 5.3 versions)
• v5.2 (TiDB 5.2 versions)
• v5.1 (TiDB 5.1 versions)
• v5.0 (TiDB 5.0 versions)
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[ti-chi-bot]

[REVIEW NOTIFICATION]

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• TomShawn

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[TomShawn]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 58299cc

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8003.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8004.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8005.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #8006.