(Update) MixStep Clarify

[KinnonYee-harness]

Description

• Please describe your changes: ________ Clarify how mixed serial and parallel work.
• Jira/GitHub Issue numbers (if any): ____ https://harnesssupport.zendesk.com/agent/tickets/93516
• Preview links/images (Internal contributors only): __________________

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[bot-gitexp-user]

Please check the Execution Link of the Pipeline for the Website Draft URL. This is located in the Preview Step behind the Harness VPN and also is available in #hdh_alerts. E.g Website Draft URL: https://unique-id--harness-developer.netlify.app. Current Draft URL is: https://68d30a87ec3d18354a7bdac5--harness-developer.netlify.app

[dewan-ahmed]

Hi @KinnonYee-harness what does this PR address? Due to the length of the page, collapsible sections keep the page manageable.

[KinnonYee-harness]

@dewan-ahmed , there's a couple things this addresses
I don't think we should collapse extremely long sections because it makes it very hard for us to correlate search terms. When trying to find information about something nested in one of the sections, it was very hard to locate for us with our knowledge, let alone the customer. I understand about keeping the article short, but I don't think it's a good practice.

We have a lot of customers trying to find the data in this page and often not being able to locate it.

The other item has to do when we mix serial and parallel steps. The article currently infers that only serial steps after the parallel deployments are declared with the added limits, but what actually happens is that ALL steps in the stage inherit those limit declarations

[dewan-ahmed]

LGTM with minor changes requested.