docs(style[shell]): Split long commands with line continuations

why: Apply the line-splitting rule from Shell Command Formatting guidelines
what:
- Split ruff check compound command in CHANGES

Author: tony

CHANGES

@@ -394,7 +394,10 @@ _Maintenance only, no bug fixes, or new features_
   via ruff v0.3.4, all automated lint fixes, including unsafe and previews were applied:
 
   ```console
-  $ ruff check --select ALL . --fix --unsafe-fixes --preview --show-fixes; ruff format .
+  $ ruff check --select ALL . \
+      --fix --unsafe-fixes \
+      --preview --show-fixes; \
+      ruff format .
   ```
 
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