Added missing methods to enrich and slm endpoints

[delvedor]

Hello!

In the spec both /_slm/policy/{name}/_execute and /_enrich/policy/{name}/_execute declare PUT as the only method supported, but in the code POST is supported as well.

elasticsearch/x-pack/plugin/ilm/src/main/java/org/elasticsearch/xpack/slm/action/RestExecuteSnapshotLifecycleAction.java

Lines 18 to 21 in b42923f

	public RestExecuteSnapshotLifecycleAction(RestController controller) {
	controller.registerHandler(RestRequest.Method.PUT, "/_slm/policy/{name}/_execute", this);
	controller.registerHandler(RestRequest.Method.POST, "/_slm/policy/{name}/_execute", this);
	}

elasticsearch/x-pack/plugin/enrich/src/main/java/org/elasticsearch/xpack/enrich/rest/RestExecuteEnrichPolicyAction.java

Lines 19 to 22 in f914172

	public RestExecuteEnrichPolicyAction(final RestController controller) {
	controller.registerHandler(RestRequest.Method.PUT, "/_enrich/policy/{name}/_execute", this);
	controller.registerHandler(RestRequest.Method.POST, "/_enrich/policy/{name}/_execute", this);
	}

cc @elastic/es-clients

[elasticmachine]

Pinging @elastic/es-core-features (:Core/Features/ILM+SLM)

[dakrone]

As mentioned in #47061, we might be deprecating and removing support for PUT.

@gwbrown do you think we should make that change for 8.0 or stick with supporting both for the long term?

[gwbrown]

PUT is the wrong verb for these actions, but 1) we support both for similar APIs (_watcher/watch/_execute for example) and 2) breaking changes always kind of suck, especially as there will never be a need to use PUT for anything else with this path, so the only reason for removing it is, in the words of Jason:

leniency is abhorrent and should be eschewed

and/or REST pedantry (which is kind of already out the window considering our main API is a GET with a body). I'm conflicted on this one. We should definitely encourage the use of POST here, but I'm not sure it's worth deprecating PUT anymore given the low cost of maintaining it and the low benefit of removing it.

[Mpdreamz]

Suggested change

	"methods": [ "PUT", "POST" ],
	"methods": [ "POST", "PUT" ],

SInce POST is preferred list it first.

[Mpdreamz]

Clients take the listed http methods in order of preference so listing POST before PUT would go along way already.