fix #7243 allow 0 as arraynode name
bug #9701 [Config] fix #7243 allow 0 as arraynode name (cordoval)

This PR was submitted for the 2.3-dev branch but it was merged into the 2.3 branch instead (closes #9701).

Discussion
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[Config] fix #7243 allow 0 as arraynode name

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #7243
| License       | MIT
| Doc PR        | no need

Commits
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a49a5c8 [Config] fix #7243 allow 0 as arraynode name