Add support for Byte Literals

[vexx32]

PR Summary

• Adds y suffix that is used to specify a numeric literal as the sbyte data type.
  • Can be combined with the existing u suffix as uy to specify the byte data type
• Adds tests to ensure the parsing for these works correctly.

Examples:

PS> 100y
100
PS> 100y.GetType().FullName
System.SByte
PS> 100uy
100
100uy.GetType().FullName
System.Byte
PS> 300uy
# Error: Invalid numeric literal

N.B.: I believe this will be a breaking change, as it means some command names (specifically, numerals suffixed with a y such as 100y) will now be interpreted as numerals instead of potential function or command names.

Ref: #7557 -- This will resolve the first part of that issue. The second portion of that issue will be solved in a follow-up PR where binary literal support is added.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Change is not breaking
• Make sure all .h, .cpp, .cs, .ps1 and .psm1 files have the correct copyright header
• This PR is ready to merge and is not Work in Progress.
  • If the PR is work in progress, please add the prefix WIP: to the beginning of the title and remove the prefix when the PR is ready.
• User-facing changes
  • Not Applicable
  • OR
  • User-facing Documentation needed
    • Issue filed - Issue link: Numeric Literal Suffixes documentation needs to be expanded MicrosoftDocs/PowerShell-Docs#2965
• Testing - New and feature
  • Not Applicable or can only be tested interactively
  • OR
  • Make sure you've added a new test if existing tests do not effectively test the code changed
    • Add [feature] if the change is significant or affects feature tests

[iSazonov]

@vexx32 Please open Issue in docs repo and add link to the PR description

[vexx32]

CodeFactor issues remaining are just in missing documentation in the enum; I can either add that to this PR or address it in follow-up PR with the rest of the changes. I would prefer to keep this one minimal, however. 😄

[iSazonov]

@vexx32 Feel free to address CodeFactor issues.

[vexx32]

Rebased for CIs && added <summary> headers for CodeFactor 😄

[iSazonov]

@daxian-dbw Could you please review the next step PR? After that we could continue and implement previously planned performance optimizations for the code in follow PR.

[vexx32]

@TravisEz13 you fellas are free to pore over it one more time, but just in case you weren't aware / didn't recall, it has been discussed a good bit and reviewed by the committee in terms of the concept over in #7557 😄

[SteveL-MSFT]

@TravisEz13 is there something specific you need the @PowerShell/powershell-committee to review for this PR?

[TravisEz13]

@SteveL-MSFT This is marked as a breaking change. The issue linked is not marked as reviewed. Looking back at the issue, it looks like this portion of the design was reviewed. Is that correct?

[vexx32]

@TravisEz13 sorry for the confusion; I requested the committee further review the ensuing discussion regarding possibly supporting underscore literal syntax and native BigInteger values. This portion was reviewed, aye. 😃

[iSazonov]

@daxian-dbw Could you please look the PR before we merge?