Auto merge of #3023 - Turbo87:sentry, r=pietroalbini

Update `sentry` to v0.21.0

see https://github.com/getsentry/sentry-rust/blob/0.21.0/CHANGELOG.md#0210

r? `@pietroalbini`

Author: bors

Cargo.lock

@@ -76,7 +76,7 @@ rand = "0.7"
 reqwest = { version = "0.10", features = ["blocking", "gzip", "json"] }
 scheduled-thread-pool = "0.2.0"
 semver = { version = "0.10", features = ["diesel", "serde"] }
-sentry = "0.20.1"
+sentry = "0.21.0"
 serde = { version = "1.0.0", features = ["derive"] }
 serde_json = "1.0.0"
 sha2 = "0.9"