Added May availability outcome to summary and new combined performance indicators page

Why is this change being made?

!126072 (diffs) deprecates the old standalone infrastructure performance indicators page. This MR updates the May content that was not copied accross and corrects the base path references for infrastructure to the correct new path.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the Maintained by section on the page being edited
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  • The when to get approval handbook section explains the workflow in more detail
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  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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