better saml map attrs messaging

[nhsiehgit]

We've now had multiple instances where this message has been really confusing.

SAML and SSO are confusing enough already.

We need to make it more clear that these map attributes are being used to link their IdP identity with their Sentry identity. In order to do so, we need them to input in the attributes from the idp identity that maps to the appropriate sentry identity attr.

hopefully this change it more clear that the attrs that failed are the sentry attributes and they need to provide a valid idp attribute to map to

[codecov[bot]]

Bundle Report

Changes will decrease total bundle size by 99.31kB :arrow_down:

Bundle name	Size	Change
sentry-webpack-bundle-array-push	26.07MB	99.31kB :arrow_down:

[getsantry[bot]]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀