bump rust-version to match upstream datafusion

Author: Michael-J-Ward

Cargo.toml

@@ -25,7 +25,7 @@ description = "Apache DataFusion DataFrame and SQL Query Engine"
 readme = "README.md"
 license = "Apache-2.0"
 edition = "2021"
-rust-version = "1.64"
+rust-version = "1.78"
 include = ["/src", "/datafusion", "/LICENSE.txt", "pyproject.toml", "Cargo.toml", "Cargo.lock"]
 
 [features]