fix(remote-ssh): disambiguate NUL escapes in the container stat test (#1901)

`cargo clippy --all-targets` denied three `clippy::octal_escapes` on the
`parse_container_file_output` fixture: the literal separated fields with
`\0`, so `\00`, `\01720000000`, and `\0644` read as possible mistaken
octal escapes. `\0` is always NUL in Rust, so the values were already
what the test intended -- clippy just cannot tell that apart from a typo.

Spell the separators `\x00` instead. `\x` consumes exactly two hex
digits, so the following digits can no longer be mistaken for part of the
escape, and the parsed fields are byte-for-byte unchanged.

The lint lives in a `#[cfg(test)]` module, so it only surfaces under
`--all-targets`, which is why the Rust Build Check never flagged it.

Author: bobleer

src/crates/services/services-integrations/src/remote_ssh/manager.rs

@@ -6034,9 +6034,11 @@ mod tests {
 
     #[test]
     fn container_special_files_are_not_reported_as_regular_files() {
-        let entry = parse_container_file_output("pipe\0/workspace/pipe\0o\00\01720000000\0644\0")
-            .unwrap()
-            .unwrap();
+        let entry = parse_container_file_output(
+            "pipe\x00/workspace/pipe\x00o\x000\x001720000000\x00644\x00",
+        )
+        .unwrap()
+        .unwrap();
 
         assert!(!entry.is_file);
         assert!(!entry.is_dir);