Use bool_from_envvar rather than bool::from_str.

Author: Alexhuszagh

src/cli.rs

@@ -87,7 +87,7 @@ pub fn parse(target_list: &TargetList) -> Result<Args> {
         .map(|s| bool_from_envvar(&s))
         .unwrap_or_default();
     let enable_doctests = env::var("CROSS_UNSTABLE_ENABLE_DOCTESTS")
-        .map(|s| bool::from_str(&s).unwrap_or_default())
+        .map(|s| bool_from_envvar(&s))
         .unwrap_or_default();
 
     Ok(Args {