Backport of Fix validation condition into v1.5

[teamterraform]

Backport

This PR is auto-generated from #34932 to be assessed for backporting due to the inclusion of the label 1.5-backport.

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@radeksimko
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The below text is copied from the body of the original PR.

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Target Release

1.8.x

Draft CHANGELOG entry

ENHANCEMENTS

This PR is aimed at fixing the validation condition specified in the style guide document. When using the example from the style guide, these are the errors that are thrown:

Error: Invalid reference in variable validation
on variables.tf line 6, in variable "web_instance_count":
6: condition = var.aws_instance_count > 1
The condition for variable "web_instance_count" can only refer to the variable itself, using var.web_instance_count.

Error: Invalid variable validation condition
on variables.tf line 6, in variable "web_instance_count":
6: condition = var.aws_instance_count > 1
The condition for variable "web_instance_count" must refer to var.web_instance_count in order to test incoming values.

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Overview of commits

• a310fed

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[radeksimko]

Depends on #34909

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