Expressions: Refinements to new functions

[olemartinorg]

Description

I missed the review window to #1209, but it turns out I had quite a few more comments to add, so I would have just made @framitdavid's day much worse, and bothered him unnecessarily before his holiday...

Here's the changes I would have suggested:

• Do not throw runtime errors unless we have to. I've said before that we should keep the expression language strict, and I still think that it should for comparisons, etc - but we should avoid runtime errors as much as possible. When a runtime error occurs (potentially deep inside a function), the entire expression fails, and a default value is returned. Since the language has no error handling (yet), we force developers to make extremely complex expressions to check if every value is null to make sure no runtime errors occcur. We can be sure that a null never ends with the given string, so these functions (such as endsWith) should just return the expected boolean instead of throwing an exception that bubbles up the stack.
• Adding support for these functions to JsonSchema. To make sure we don't miss that for future built-in functions, I added a unit test to check the schema and validate against it.
• Making the last parameter for the round function optional (and implementing support for that in the validator), so that we don't have to pass null when you want to round to the nearest integer.
• Returning nb as the default language if the profile does not have any information. That's the default in our apps as well, and null as the default here is not really useful.
• Fixing autocompletion for function names in vscode by using anyOf instead of oneOf

Related Issue(s)

• New functions to expressions #1209
• Expressions: New simple functions #1176
• Some tests here are disabled, but should be solved by Tech debt: Language support #1218

Verification/QA

• Manual functionality testing
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  • No automatic tests are needed here (no functional changes/additions)
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• UU/WCAG (follow these guidelines until we have our own)
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  • Has been added/updated
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• Changes/additions to component properties
  • Changes are reflected in both src/layout/layout.d.ts and layout.schema.v1.json, and these are all backwards-compatible
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[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
2 Code Smells

93.3% Coverage
0.0% Duplication

[bjosttveit]

Great stuff 🥇