send a User-Agent on all requests

amazing that this wasn't done in the first place. a lack of a UA is
suspicious and some providers may block our requests just for the sake
of no UA.

Signed-off-by: strawberry <strawberry@puppygock.gay>

src/service/globals/mod.rs

@@ -542,7 +542,12 @@ fn reqwest_client_builder(config: &Config) -> Result<reqwest::ClientBuilder> {
     let mut reqwest_client_builder = reqwest::Client::builder()
         .pool_max_idle_per_host(0)
         .connect_timeout(Duration::from_secs(60))
-        .timeout(Duration::from_secs(60 * 5));
+        .timeout(Duration::from_secs(60 * 5))
+        .user_agent(concat!(
+            env!("CARGO_PKG_NAME"),
+            "/",
+            env!("CARGO_PKG_VERSION")
+        ));
 
     if let Some(proxy) = config.proxy.to_proxy()? {
         reqwest_client_builder = reqwest_client_builder.proxy(proxy);