models/krate: Adjust InvalidFeature::Empty error message

Author: Turbo87

src/models/krate.rs

@@ -513,7 +513,7 @@ impl CrateVersions for [Crate] {
 
 #[derive(Debug, Eq, PartialEq, thiserror::Error)]
 pub enum InvalidFeature {
-    #[error("feature cannot be an empty")]
+    #[error("feature cannot be empty")]
     Empty,
     #[error(
         "invalid character `{0}` in feature `{1}`, the first character must be \

src/tests/krate/publish/snapshots/all__krate__publish__features__empty_feature_name.snap

@@ -5,7 +5,7 @@ expression: response.into_json()
 {
   "errors": [
     {
-      "detail": "feature cannot be an empty"
+      "detail": "feature cannot be empty"
     }
   ]
 }