remove/deprecate crawler disable environment (#11214)

with changes present to automatically throttle crawler
at runtime, there is no need to have an environment
value to disable crawling. crawling is a fundamental
piece for healing, lifecycle and many other features
there is no good reason anyone would need to disable
this on a production system.

* Apply suggestions from code review

cmd/admin-bucket-handlers.go

@@ -23,9 +23,7 @@ import (
 	"net/http"
 
 	"github.com/gorilla/mux"
-	"github.com/minio/minio/cmd/config"
 	"github.com/minio/minio/cmd/logger"
-	"github.com/minio/minio/pkg/env"
 	iampolicy "github.com/minio/minio/pkg/iam/policy"
 	"github.com/minio/minio/pkg/madmin"
 )
@@ -54,12 +52,6 @@ func (a adminAPIHandlers) PutBucketQuotaConfigHandler(w http.ResponseWriter, r *
 	vars := mux.Vars(r)
 	bucket := vars["bucket"]
 
-	// Turn off quota commands if data usage info is unavailable.
-	if env.Get(envDataUsageCrawlConf, config.EnableOn) == config.EnableOff {
-		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminBucketQuotaDisabled), r.URL)
-		return
-	}
-
 	if _, err := objectAPI.GetBucketInfo(ctx, bucket); err != nil {
 		writeErrorResponseJSON(ctx, w, toAPIError(ctx, err), r.URL)
 		return