docs: fix 'enviroment' typo in Ping Identity SAML URL

[mrchatam]

Summary

Correct placeholder spelling in the Ping Identity SAML Target Application URL example: {enviroment} → {environment}.

Test plan

• Confirmed the surrounding URL template is otherwise unchanged
• Single typo fix only

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Note

Low Risk
Documentation-only spelling fix with no runtime or security impact.

Overview
Fixes a typo in the IdP-initiated SSO section of the Ping Identity SAML guide: the Target Application URL placeholder is corrected from {enviroment} to {environment} so it matches the spelling used elsewhere in the same section (e.g. the apps.pingone.com URL).

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[mrchatam]

Closing: Redis CLA is not signed for this account, so these docs PRs cannot proceed. Will reopen after CLA is signed if still needed.