Update prometheus, removing spin dependency

Changelog: https://github.com/tikv/rust-prometheus/blob/master/CHANGELOG.md#0100

Author: jyn514

Cargo.lock

@@ -39,7 +39,7 @@ toml = "0.5"
 schemamama = "0.3"
 schemamama_postgres = "0.3"
 systemstat = "0.1.4"
-prometheus = { version = "0.9.0", default-features = false }
+prometheus = { version = "0.10.0", default-features = false }
 rustwide = "0.10.0"
 mime_guess = "2"
 dotenv = "0.15"