Rename ruff_python_semantic's Context struct to SemanticModel (#4565)

crates/ruff_cache/tests/cache_key.rs

@@ -1,8 +1,9 @@
-use ruff_cache::{CacheKey, CacheKeyHasher};
-use ruff_macros::CacheKey;
 use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};
 
+use ruff_cache::{CacheKey, CacheKeyHasher};
+use ruff_macros::CacheKey;
+
 #[derive(CacheKey, Hash)]
 struct UnitStruct;