SerDe: fix skipping tree node in JSON

[flo-dup]

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

Does this PR already have an issue describing the problem?
No, but PR #3211 introduced a unit test which fails.

What kind of change does this PR introduce?
Bug fix

What is the current behavior?
Call on skipChildNodes on a JSON file while on a node having scalar value attributes leads to an exception

What is the new behavior (if this is a feature change)?
Call on skipChildNodes on a JSON file while on a node having scalar value attributes skip the whole current node. Hence skipChildNodes has been renamed into skipNode.

Does this PR introduce a breaking change or deprecate an API?

• Yes
• No

If yes, please check if the following requirements are fulfilled

• The Breaking Change or Deprecated label has been added
• The migration steps are described in the following section

What changes might users need to make in their application due to this PR? (migration steps)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
86.5% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud