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Fixes documentation. I wrote `env_clear` when I meant `env_remove`. Good catch.

Co-authored-by: Josh Stone <cuviper@gmail.com>

Author: schneems

library/std/src/process.rs

@@ -1031,7 +1031,7 @@ impl Command {
     /// process.
     ///
     /// Each element is a tuple key/value pair `(&OsStr, Option<&OsStr>)`. A [`None`] value
-    /// indicates its key was explicitly removed via [`Command::env_clear`]. The associated key for
+    /// indicates its key was explicitly removed via [`Command::env_remove`]. The associated key for
     /// the [`None`] value will no longer inherit from its parent process.
     ///
     /// An empty iterator can indicate that no explicit mappings were added or that