Align docs with tags provider and contributor changes

Closes gh-33281

spring-boot-project/spring-boot-docs/src/docs/asciidoc/actuator/metrics.adoc

@@ -768,8 +768,9 @@ By default, Spring MVC related metrics are tagged with the following information
 | The request's URI template prior to variable substitution, if possible (for example, `/api/person/\{id}`)
 |===
 
-To add to the default tags, provide one or more ``@Bean``s that implement `WebMvcTagsContributor`.
-To replace the default tags, provide a `@Bean` that implements `WebMvcTagsProvider`.
+To add to the default tags, provide a `@Bean` that extends `DefaultServerRequestObservationConvention` from the `org.springframework.http.observation` package.
+To replace the default tags, provide a `@Bean` that implements `GlobalObservationConvention<ServerRequestObservationContext>`.
+
 
 TIP: In some cases, exceptions handled in web controllers are not recorded as request metrics tags.
 Applications can opt in and record exceptions by <<web#web.servlet.spring-mvc.error-handling, setting handled exceptions as request attributes>>.
@@ -807,8 +808,8 @@ By default, WebFlux related metrics are tagged with the following information:
 | The request's URI template prior to variable substitution, if possible (for example, `/api/person/\{id}`)
 |===
 
-To add to the default tags, provide one or more beans that implement `WebFluxTagsContributor`.
-To replace the default tags, provide a bean that implements `WebFluxTagsProvider`.
+To add to the default tags, provide a `@Bean` that extends `DefaultServerRequestObservationConvention` from the `org.springframework.http.observation.reactive` package.
+To replace the default tags, provide a `@Bean` that implements `GlobalObservationConvention<ServerRequestObservationContext>`.
 
 TIP: In some cases, exceptions handled in controllers and handler functions are not recorded as request metrics tags.
 Applications can opt in and record exceptions by <<web#web.reactive.webflux.error-handling, setting handled exceptions as request attributes>>.
@@ -882,8 +883,8 @@ By default, metrics generated by an instrumented client are tagged with the foll
 | The request's URI template prior to variable substitution, if possible (for example, `/api/person/\{id}`)
 |===
 
-To customize the tags, and depending on your choice of client, you can provide a `@Bean` that implements `RestTemplateExchangeTagsProvider` or `WebClientExchangeTagsProvider`.
-There are convenience static functions in `RestTemplateExchangeTags` and `WebClientExchangeTags`.
+To customize the tags when using `RestTemplate`, provide a `@Bean` that implements `ClientRequestObservationConvention` from the `org.springframework.http.client.observation` package.
+To customize the tags when using `WebClient`, provide a `@Bean` that implements `ClientRequestObservationConvention` from the `org.springframework.web.reactive.function.client` package.