Expect indented case block instead of match stmt (#11033)

## Summary

This PR adds a new `Clause::Case` and uses it to parse the body of a
`case` block. Earlier, it was using `Match` which would give an
incorrect error message like:

```
  |
1 | match subject:
2 |     case 1:
3 |     case 2: ...
  |     ^^^^ Syntax Error: Expected an indented block after `match` statement
  |
```

## Test Plan

Add test case and update the snapshot.

Author: dhruvmanila

crates/ruff_python_parser/resources/inline/err/case_expect_indented_block.py

@@ -0,0 +1,3 @@
+match subject:
+    case 1:
+    case 2: ...

crates/ruff_python_parser/src/parser/statement.rs

@@ -2492,7 +2492,12 @@ impl<'src> Parser<'src> {
         };
 
         self.expect(TokenKind::Colon);
-        let body = self.parse_body(Clause::Match);
+
+        // test_err case_expect_indented_block
+        // match subject:
+        //     case 1:
+        //     case 2: ...
+        let body = self.parse_body(Clause::Case);
 
         ast::MatchCase {
             pattern,
@@ -3363,7 +3368,7 @@ enum Clause {
     Class,
     While,
     FunctionDef,
-    Match,
+    Case,
     Try,
     Except,
     Finally,
@@ -3380,7 +3385,7 @@ impl Display for Clause {
             Clause::Class => write!(f, "`class` definition"),
             Clause::While => write!(f, "`while` statement"),
             Clause::FunctionDef => write!(f, "function definition"),
-            Clause::Match => write!(f, "`match` statement"),
+            Clause::Case => write!(f, "`case` block"),
             Clause::Try => write!(f, "`try` statement"),
             Clause::Except => write!(f, "`except` clause"),
             Clause::Finally => write!(f, "`finally` clause"),

crates/ruff_python_parser/tests/snapshots/invalid_syntax@case_expect_indented_block.py.snap

@@ -0,0 +1,84 @@
+---
+source: crates/ruff_python_parser/tests/fixtures.rs
+input_file: crates/ruff_python_parser/resources/inline/err/case_expect_indented_block.py
+---
+## AST
+
+```
+Module(
+    ModModule {
+        range: 0..43,
+        body: [
+            Match(
+                StmtMatch {
+                    range: 0..42,
+                    subject: Name(
+                        ExprName {
+                            range: 6..13,
+                            id: "subject",
+                            ctx: Load,
+                        },
+                    ),
+                    cases: [
+                        MatchCase {
+                            range: 19..26,
+                            pattern: MatchValue(
+                                PatternMatchValue {
+                                    range: 24..25,
+                                    value: NumberLiteral(
+                                        ExprNumberLiteral {
+                                            range: 24..25,
+                                            value: Int(
+                                                1,
+                                            ),
+                                        },
+                                    ),
+                                },
+                            ),
+                            guard: None,
+                            body: [],
+                        },
+                        MatchCase {
+                            range: 31..42,
+                            pattern: MatchValue(
+                                PatternMatchValue {
+                                    range: 36..37,
+                                    value: NumberLiteral(
+                                        ExprNumberLiteral {
+                                            range: 36..37,
+                                            value: Int(
+                                                2,
+                                            ),
+                                        },
+                                    ),
+                                },
+                            ),
+                            guard: None,
+                            body: [
+                                Expr(
+                                    StmtExpr {
+                                        range: 39..42,
+                                        value: EllipsisLiteral(
+                                            ExprEllipsisLiteral {
+                                                range: 39..42,
+                                            },
+                                        ),
+                                    },
+                                ),
+                            ],
+                        },
+                    ],
+                },
+            ),
+        ],
+    },
+)
+```
+## Errors
+
+  |
+1 | match subject:
+2 |     case 1:
+3 |     case 2: ...
+  |     ^^^^ Syntax Error: Expected an indented block after `case` block
+  |