Recategorize runtime-string-union to TCH010 (#9721)

## Summary

This rule was added to `flake8-type-checking` as `TC010`. We're about to
stabilize it, so we might as well use the correct code.

See: #9573.

crates/ruff_linter/resources/test/fixtures/flake8_type_checking/TCH010_1.py

@@ -0,0 +1,18 @@
+from __future__ import annotations
+
+from typing import TypeVar
+
+
+x: "int" | str  # TCH010
+x: ("int" | str) | "bool"  # TCH010
+
+
+def func():
+    x: "int" | str  # OK
+
+
+z: list[str, str | "int"] = []  # TCH010
+
+type A = Value["int" | str]  # OK
+
+OldS = TypeVar('OldS', int | 'str', str)  # TCH010

crates/ruff_linter/resources/test/fixtures/flake8_type_checking/TCH010_2.py

@@ -0,0 +1,16 @@
+from typing import TypeVar
+
+
+x: "int" | str  # TCH010
+x: ("int" | str) | "bool"  # TCH010
+
+
+def func():
+    x: "int" | str  # OK
+
+
+z: list[str, str | "int"] = []  # TCH010
+
+type A = Value["int" | str]  # OK
+
+OldS = TypeVar('OldS', int | 'str', str)  # TCH010

crates/ruff_linter/src/codes.rs

@@ -841,7 +841,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Flake8TypeChecking, "003") => (RuleGroup::Stable, rules::flake8_type_checking::rules::TypingOnlyStandardLibraryImport),
         (Flake8TypeChecking, "004") => (RuleGroup::Stable, rules::flake8_type_checking::rules::RuntimeImportInTypeCheckingBlock),
         (Flake8TypeChecking, "005") => (RuleGroup::Stable, rules::flake8_type_checking::rules::EmptyTypeCheckingBlock),
-        (Flake8TypeChecking, "006") => (RuleGroup::Stable, rules::flake8_type_checking::rules::RuntimeStringUnion),
+        (Flake8TypeChecking, "010") => (RuleGroup::Stable, rules::flake8_type_checking::rules::RuntimeStringUnion),
 
         // tryceratops
         (Tryceratops, "002") => (RuleGroup::Stable, rules::tryceratops::rules::RaiseVanillaClass),

crates/ruff_linter/src/rule_redirects.rs

@@ -99,5 +99,6 @@ static REDIRECTS: Lazy<HashMap<&'static str, &'static str>> = Lazy::new(|| {
         ("T003", "FIX003"),
         ("T004", "FIX004"),
         ("RUF011", "B035"),
+        ("TCH006", "TCH010"),
     ])
 });

crates/ruff_linter/src/rules/flake8_type_checking/mod.rs

@@ -35,8 +35,8 @@ mod tests {
     #[test_case(Rule::RuntimeImportInTypeCheckingBlock, Path::new("TCH004_8.py"))]
     #[test_case(Rule::RuntimeImportInTypeCheckingBlock, Path::new("TCH004_9.py"))]
     #[test_case(Rule::RuntimeImportInTypeCheckingBlock, Path::new("quote.py"))]
-    #[test_case(Rule::RuntimeStringUnion, Path::new("TCH006_1.py"))]
-    #[test_case(Rule::RuntimeStringUnion, Path::new("TCH006_2.py"))]
+    #[test_case(Rule::RuntimeStringUnion, Path::new("TCH010_1.py"))]
+    #[test_case(Rule::RuntimeStringUnion, Path::new("TCH010_2.py"))]
     #[test_case(Rule::TypingOnlyFirstPartyImport, Path::new("TCH001.py"))]
     #[test_case(Rule::TypingOnlyStandardLibraryImport, Path::new("TCH003.py"))]
     #[test_case(Rule::TypingOnlyStandardLibraryImport, Path::new("init_var.py"))]

crates/ruff_linter/src/rules/flake8_type_checking/snapshots/ruff_linter__rules__flake8_type_checking__tests__runtime-string-union_TCH010_1.py.snap

@@ -0,0 +1,12 @@
+---
+source: crates/ruff_linter/src/rules/flake8_type_checking/mod.rs
+---
+TCH010_1.py:18:30: TCH010 Invalid string member in `X | Y`-style union type
+   |
+16 | type A = Value["int" | str]  # OK
+17 | 
+18 | OldS = TypeVar('OldS', int | 'str', str)  # TCH010
+   |                              ^^^^^ TCH010
+   |
+
+

crates/ruff_linter/src/rules/flake8_type_checking/snapshots/ruff_linter__rules__flake8_type_checking__tests__runtime-string-union_TCH010_2.py.snap

@@ -0,0 +1,41 @@
+---
+source: crates/ruff_linter/src/rules/flake8_type_checking/mod.rs
+---
+TCH010_2.py:4:4: TCH010 Invalid string member in `X | Y`-style union type
+  |
+4 | x: "int" | str  # TCH010
+  |    ^^^^^ TCH010
+5 | x: ("int" | str) | "bool"  # TCH010
+  |
+
+TCH010_2.py:5:5: TCH010 Invalid string member in `X | Y`-style union type
+  |
+4 | x: "int" | str  # TCH010
+5 | x: ("int" | str) | "bool"  # TCH010
+  |     ^^^^^ TCH010
+  |
+
+TCH010_2.py:5:20: TCH010 Invalid string member in `X | Y`-style union type
+  |
+4 | x: "int" | str  # TCH010
+5 | x: ("int" | str) | "bool"  # TCH010
+  |                    ^^^^^^ TCH010
+  |
+
+TCH010_2.py:12:20: TCH010 Invalid string member in `X | Y`-style union type
+   |
+12 | z: list[str, str | "int"] = []  # TCH010
+   |                    ^^^^^ TCH010
+13 | 
+14 | type A = Value["int" | str]  # OK
+   |
+
+TCH010_2.py:16:30: TCH010 Invalid string member in `X | Y`-style union type
+   |
+14 | type A = Value["int" | str]  # OK
+15 | 
+16 | OldS = TypeVar('OldS', int | 'str', str)  # TCH010
+   |                              ^^^^^ TCH010
+   |
+
+