[ruff] Stabilize unnecessary-cast-to-int (RUF046) (#16649)

Summary
--

Stabilizes RUF046 and moves its test to the right place. The docs look
good.

Test Plan
--

2 closed newline/whitespace issues from early January and 1 closed issue
about really being multiple rules, but otherwise no recent issues or
PRs.

Author: ntBre

crates/ruff_linter/src/codes.rs

@@ -1001,7 +1001,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Ruff, "041") => (RuleGroup::Preview, rules::ruff::rules::UnnecessaryNestedLiteral),
         (Ruff, "043") => (RuleGroup::Preview, rules::ruff::rules::PytestRaisesAmbiguousPattern),
         (Ruff, "045") => (RuleGroup::Preview, rules::ruff::rules::ImplicitClassVarInDataclass),
-        (Ruff, "046") => (RuleGroup::Preview, rules::ruff::rules::UnnecessaryCastToInt),
+        (Ruff, "046") => (RuleGroup::Stable, rules::ruff::rules::UnnecessaryCastToInt),
         (Ruff, "047") => (RuleGroup::Preview, rules::ruff::rules::NeedlessElse),
         (Ruff, "048") => (RuleGroup::Preview, rules::ruff::rules::MapIntVersionParsing),
         (Ruff, "049") => (RuleGroup::Preview, rules::ruff::rules::DataclassEnum),

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

@@ -83,6 +83,7 @@ mod tests {
     #[test_case(Rule::InvalidAssertMessageLiteralArgument, Path::new("RUF040.py"))]
     #[test_case(Rule::UnnecessaryNestedLiteral, Path::new("RUF041.py"))]
     #[test_case(Rule::UnnecessaryNestedLiteral, Path::new("RUF041.pyi"))]
+    #[test_case(Rule::UnnecessaryCastToInt, Path::new("RUF046.py"))]
     #[test_case(Rule::NeedlessElse, Path::new("RUF047_if.py"))]
     #[test_case(Rule::NeedlessElse, Path::new("RUF047_for.py"))]
     #[test_case(Rule::NeedlessElse, Path::new("RUF047_while.py"))]
@@ -426,7 +427,6 @@ mod tests {
     #[test_case(Rule::UnnecessaryRegularExpression, Path::new("RUF055_0.py"))]
     #[test_case(Rule::UnnecessaryRegularExpression, Path::new("RUF055_1.py"))]
     #[test_case(Rule::UnnecessaryRegularExpression, Path::new("RUF055_2.py"))]
-    #[test_case(Rule::UnnecessaryCastToInt, Path::new("RUF046.py"))]
     #[test_case(Rule::PytestRaisesAmbiguousPattern, Path::new("RUF043.py"))]
     #[test_case(Rule::UnnecessaryRound, Path::new("RUF057.py"))]
     #[test_case(Rule::DataclassEnum, Path::new("RUF049.py"))]