Use to_owned consistently

Summary: String::from takes a wide range of types. `to_owned` is more specific, and what we use nearly all the time, so make it a little more consistent.

Reviewed By: aniketmathur

Differential Revision: D54483201

fbshipit-source-id: f20409d7977d26dca3491ca6d184fe6729d22015

btd/src/rerun.rs

@@ -285,7 +285,7 @@ mod tests {
             }),
             TargetsEntry::Error(BuckError {
                 package: Package::new("fbcode//broken"),
-                error: String::from("broken"),
+                error: "broken".to_owned(),
             }),
         ];
         let base = Targets::new(target_entries);
@@ -331,7 +331,7 @@ mod tests {
             }),
             TargetsEntry::Error(BuckError {
                 package: Package::new("fbcode//broken"),
-                error: String::from("broken"),
+                error: "broken".to_owned(),
             }),
         ];
         let base = Targets::new(target_entries);