Updates schema to enforce names as required RFC1123 values

[cdavernas]

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Discussion or Issue link:
#671 #685

What this PR does / why we need it:

• Enforce names of states, events, functions, actions, branches and conditions to be required and to follow the RFC1123 DNS label format.

[gibson042]

RFC 1123 does not include any lowercasing requirement; did you intend to make this a further restriction?

I think some text is also warranted regarding RFC 5890 R-LDH labels (whose third and fourth characters are both "-") such as xn--bcher-kva (which is further an XN-label and valid A-label representing "bücher") and we--like--it (which is neither but is still subject to the "MUST NOT be processed as ordinary LDH labels by IDNA-conforming programs" restriction).

I don't think it matters whether they are allowed or rejected, but some software does treat them specially so it's worth being explicit.

[cdavernas]

@gibson042 I thought it did, or at least does it's k8s flavor:

https://kubernetes.io/docs/concepts/overview/working-with-objects/names/#:~:text=RFC%201123%20Label%20Names&text=in%20RFC%201123.-,This%20means%20the%20name%20must%3A,start%20with%20an%20alphanumeric%20character

Anyways, I do think adding the lowercase restriction is a must, as i believe it could help ensure invariance, especially on exotic systems.

It's not however a strong preference, and I'm obviously open to any and all opinion for and against ;)

As for the double dashes, I tend to believe it's safe to forbid its use altogether, like with the k8s regex I'm using in the PR. WDYT?

[gibson042]

👍

[gibson042]

@cdavernas Thanks for the updates!

[cdavernas]

@gibson042 No, thanks to you for both the comments and the suggested edits ❤️

[github-actions]

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