Format continue statement (#5165)

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## Summary

Format `continue` statement.

## Test Plan

`continue` is used already in some tests, but if a new test is needed I
could add it.

---------

Co-authored-by: konstin <konstin@mailbox.org>

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comments2_py.snap

@@ -303,7 +303,7 @@ instruction()#comment with bad spacing
          pass
      # no newline before or after
      short = [
-@@ -91,75 +88,29 @@
+@@ -91,48 +88,14 @@
      ]
  
      # no newline after
@@ -356,10 +356,8 @@ instruction()#comment with bad spacing
 +    lcomp3 = [i for i in []]
      while True:
          if False:
--            continue
-+            NOT_YET_IMPLEMENTED_StmtContinue
- 
-             # and round and round we go
+             continue
+@@ -141,25 +104,13 @@
          # and round and round we go
  
      # let's return
@@ -502,7 +500,7 @@ def inline_comments_in_brackets_ruin_everything():
     lcomp3 = [i for i in []]
     while True:
         if False:
-            NOT_YET_IMPLEMENTED_StmtContinue
+            continue
 
             # and round and round we go
         # and round and round we go

crates/ruff_python_formatter/src/statement/stmt_continue.rs

@@ -1,12 +1,13 @@
-use crate::{not_yet_implemented, FormatNodeRule, PyFormatter};
-use ruff_formatter::{write, Buffer, FormatResult};
+use crate::{FormatNodeRule, PyFormatter};
+use ruff_formatter::prelude::text;
+use ruff_formatter::{Format, FormatResult};
 use rustpython_parser::ast::StmtContinue;
 
 #[derive(Default)]
 pub struct FormatStmtContinue;
 
 impl FormatNodeRule<StmtContinue> for FormatStmtContinue {
-    fn fmt_fields(&self, item: &StmtContinue, f: &mut PyFormatter) -> FormatResult<()> {
-        write!(f, [not_yet_implemented(item)])
+    fn fmt_fields(&self, _item: &StmtContinue, f: &mut PyFormatter) -> FormatResult<()> {
+        text("continue").fmt(f)
     }
 }