AUTO_INCREMENT: update keyword auto_increment to CAPS

[kana112233]

What is changed, added or deleted?

did: update keyword auto_increment to AUTO_INCREMENT
why: issue: #699
"In #695 we determined that SQL keywords should be in all caps. There are a number of pages that require updating."

What is the related PR or file link(s)?

N/A

Which version does your change affect?

dev/v1.0/v2.0/v2.1/v2.1-legacy/v3.0/v3.1

[yikeke]

Thanks for your contribution! @kana112233 Please sign the CLA so we can get this pull request merged later.

[yikeke]

LGTM

[kana112233]

sign the CLA

I can't sign the CLA by username: makey22112, #1750 is new PR.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
2 out of 3 committers have signed the CLA.

✅ yikeke
✅ kana112233
❌ makey22112

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