v15 backport: Online DDL: fix 'vtctlclient OnlineDDL' template queries (#11889)

[shlomi-noach]

backport of #11889

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Description

At some point the behavior of sqlparser.QueryMatchesTemplates(...) changed such that if the template has multiple recurring 'val' values, the new behavior expects them to be equal.

This breaks the vtctlclient OnlineDDL behavior, because OnlineDDL's query templates used recurring 'val'. The templates are now updated, and a new unit test validates their behavior.

Related Issue(s)

#11893
#6926

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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