chore: add revocation endpoint to oauth well-known (coder#20561)

Was added to apps endpoints, but not the wider site ones. This is a site
wide oauth route

Author: Emyrk

coderd/apidoc/docs.go

@@ -18,6 +18,7 @@ func GetAuthorizationServerMetadata(accessURL *url.URL) http.HandlerFunc {
 			AuthorizationEndpoint:             accessURL.JoinPath("/oauth2/authorize").String(),
 			TokenEndpoint:                     accessURL.JoinPath("/oauth2/tokens").String(),
 			RegistrationEndpoint:              accessURL.JoinPath("/oauth2/register").String(), // RFC 7591
+			RevocationEndpoint:                accessURL.JoinPath("/oauth2/revoke").String(),   // RFC 7009
 			ResponseTypesSupported:            []string{"code"},
 			GrantTypesSupported:               []string{"authorization_code", "refresh_token"},
 			CodeChallengeMethodsSupported:     []string{"S256"},

coderd/apidoc/swagger.json

@@ -262,6 +262,7 @@ type OAuth2AuthorizationServerMetadata struct {
 	AuthorizationEndpoint             string   `json:"authorization_endpoint"`
 	TokenEndpoint                     string   `json:"token_endpoint"`
 	RegistrationEndpoint              string   `json:"registration_endpoint,omitempty"`
+	RevocationEndpoint                string   `json:"revocation_endpoint,omitempty"`
 	ResponseTypesSupported            []string `json:"response_types_supported"`
 	GrantTypesSupported               []string `json:"grant_types_supported"`
 	CodeChallengeMethodsSupported     []string `json:"code_challenge_methods_supported"`