msrv: set rust-version = 1.60

BurntSushi · BurntSushi · commit 521294f87b3e · 2023-02-13T21:34:10.000-05:00
diff --git a/Cargo.toml b/Cargo.toml
@@ -13,6 +13,7 @@ categories = ["encoding", "parser-implementations"]
 exclude = ["/.github", "/ci/*", "/scripts/*"]
 edition = "2021"
 resolver = "2"
+rust-version = "1.60"
 
 [workspace]
 members = ["csv-core", "csv-index"]
