Fix Metrics Dictionary URL

doc/api/usage_data.md

@@ -13,7 +13,7 @@ The Service Data API is associated with [Service Ping](../development/service_pi
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/57270) in GitLab 13.11.
 
-Export all metric definitions as a single YAML file, similar to the [Metrics Dictionary](https://metrics.gitlab.com/index.html), for easier importing.
+Export all metric definitions as a single YAML file, similar to the [Metrics Dictionary](https://metrics.gitlab.com/), for easier importing.
 
 ```plaintext
 GET /usage_data/metric_definitions

doc/development/service_ping/metrics_dictionary.md

@@ -7,7 +7,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 # Metrics Dictionary Guide
 
 [Service Ping](index.md) metrics are defined in the
-[Metrics Dictionary](https://metrics.gitlab.com/index.html).
+[Metrics Dictionary](https://metrics.gitlab.com/).
 This guide describes the dictionary and how it's implemented.
 
 ## Metrics Definition and validation

doc/development/service_ping/review_guidelines.md

@@ -14,7 +14,7 @@ general best practices for code reviews, refer to our [code review guide](../cod
 ## Resources for reviewers
 
 - [Service Ping Guide](index.md)
-- [Metrics Dictionary](https://metrics.gitlab.com/index.html)
+- [Metrics Dictionary](https://metrics.gitlab.com/)
 
 ## Review process