Link the 19 API-key access-review connector docs

Each of these providers ships an API-key connection path and a driver, but
no Registration carried a DocumentationURL, so the console rendered no
"how do I get this token" link on the connect dialog. probo.com now has a
page per provider, so point each Registration at it.

Slugs are passed explicitly rather than derived from the enum, per
accessReviewDocsURL's contract, so BETTER_STACK maps to better-stack and
INCIDENT_IO to incident-io.

Signed-off-by: Aurélien Sibiril <81782+aureliensibiril@users.noreply.github.com>

pkg/connector/provider/clickhouse.go

@@ -31,9 +31,10 @@ import (
 
 func clickhouseRegistration() *Registration {
 	return &Registration{
-		Provider:       coredata.ConnectorProviderClickHouse,
-		DisplayName:    "ClickHouse Cloud",
-		SupportsAPIKey: true,
+		Provider:         coredata.ConnectorProviderClickHouse,
+		DisplayName:      "ClickHouse Cloud",
+		DocumentationURL: accessReviewDocsURL("clickhouse"),
+		SupportsAPIKey:   true,
 		// ClickHouse Cloud's control-plane API authenticates with HTTP Basic
 		// auth where the credential is keyId:keySecret. APIKeyBasicAuthUserPass
 		// makes the APIKeyConnection base64 the verbatim "keyId:keySecret"