chore(351): add service reliability standard

[oluashiruHO]

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[daniel-ac-martin]

I wonder whether this is really a single standard. (I defer to others on the definitions we are using.)

To me 'service reliability' is a goal that we are trying to achieve, rather than a specific standard. So I wonder if this should be broken down.

I also think this assumes that every service has a high availability requirement, which isn't really true. If we were to consider a back-end process (no human user), how many of these points remain as MUSTs?

[robertdeniszczyc2]

Hi,

I started providing feedback on this in the PR, but I think a lot of my thoughts are already captured by @daniel-ac-martin above (#352 (comment)).

Service reliability is already mentioned in the MaC Pattern and I feel some of the MUSTs in this feel closer to a Pattern than a Standard.

I'm happy to talk through in more detail, but I feel this needs some more refinement if it is to be implemented as a Standard.

Thanks,
Rob

[LDP0wer]

I've add comments from MBTP perspective. There's some lines in here which were explicitly to support QAT testing these Standards, which we won't need. Also offered rewording suggestions where our original wording was a bit clunky.

[LDP0wer]

I've left a few comments on small formatting/grammar suggestions.

[jeff-horton-ho-sas]

Updates to make content consistent with the GOV.UK style guide, especially:

• https://www.gov.uk/guidance/style-guide/a-to-z-of-gov-uk-style#bullet-points-steps
• https://www.gov.uk/guidance/style-guide/a-to-z-of-gov-uk-style#capitalisation