Fix typos (#638)

Running `pre-commit` caught a couple things

cargo-insta/Cargo.toml

@@ -38,4 +38,4 @@ walkdir = "2.3.1"
 similar= "2.2.1"
 itertools = "0.10.0"
 termcolor = "1.1.2"
-os_pipe = "0.9.0"
+os_pipe = "0.9.0"

cargo-insta/src/cli.rs

@@ -469,7 +469,7 @@ fn handle_target_args<'a>(
         .iter()
         .map(|x| {
             if let Some(no_period) = x.strip_prefix(".") {
-                eprintln!("`{}` supplied as an extenstion. This will use `foo.{}` as file names; likely you want `{}` instead.", x, x, no_period)
+                eprintln!("`{}` supplied as an extension. This will use `foo.{}` as file names; likely you want `{}` instead.", x, x, no_period)
             };
             x.as_str()
         })

cargo-insta/tests/main.rs

@@ -11,11 +11,15 @@
 ///     .args(["test"])
 ///     .stderr(Stdio::piped())
 ///
-/// assert!(String::from_utf8_lossy(&output.stderr).contains("info: 2 snapshots to review")
+/// assert!(
+///     String::from_utf8_lossy(&output.stderr).contains("info: 2 snapshots to review"),
+///    "{}",
+///     String::from_utf8_lossy(&output.stderr)
+/// );
 /// ```
 ///
 /// Often we want to see output from the test commands we run here; for example
-/// a `dbg!` statement we add while debugging. Cargo by default hides the output
+/// a `dbg` statement we add while debugging. Cargo by default hides the output
 /// of passing tests.
 /// - Like any test, to forward the output of a passing outer test (i.e. one of
 ///   the `#[test]`s in this file) to the terminal, pass `--nocapture` to the

insta/src/runtime.rs

@@ -476,7 +476,7 @@ impl<'a> SnapshotAssertionContext<'a> {
     }
 
     /// Removes any old .snap.new.* files that belonged to previous pending snapshots. This should
-    /// only ever remove maxium one file because we do this every time before we create a new
+    /// only ever remove maximum one file because we do this every time before we create a new
     /// pending snapshot.
     pub fn cleanup_previous_pending_binary_snapshots(&self) -> Result<(), Box<dyn Error>> {
         if let Some(ref path) = self.snapshot_file {