[Uptime][Bug] Full size screenshot label is misleading

[paulb-elastic]

When clicking on the thumbnail image to get the full size image, the label at the bottom (with controls to view the prev/next) seems to include the total number of steps but with no of between them, which just makes the label confusing.

This is a bug in the current implementation (there is also a separate, larger enhancement for this label/control in elastic/uptime#291).

For example, clicking on the thumbnail for step 1 of a 9 step UJ:

I would suggest the scope of this fix is just to add of between the current step number and the total number of steps.

@katrin-freihofner are you ok with this more urgent fix, until we get elastic/uptime#291 done?

[elasticmachine]

Pinging @elastic/uptime (Team:uptime)

[paulb-elastic]

This was identified whilst looking at #90978, although is not specific to that PR

[katrin-freihofner]

@katrin-freihofner are you ok with this more urgent fix, until we get elastic/uptime#291 done?

Yes, makes sense