Clarify that beta builds can be picked up by version (#1023)

Author: apiraino

src/release/crater.md

@@ -10,12 +10,12 @@ First, file a new issue titled "Crater runs for 1.x" ([example](https://github.c
 A crater run for beta should be started as soon as we have beta out. Use the following craterbot
 invocations.
 
-$BETA_VERSION is e.g. 1.40.0-1, increment the 1 if it's not the first beta crater run, you can also
+$BETA_VERSION is e.g. 1.81.0-1, increment the 1 if it's not the first beta crater run, you can also
 use the auto-incremented counter on the beta `rustc --version`.
 
-$STABLE is e.g. 1.39.0 (the stable release)
-$BETA is beta-YYYY-MM-DD, get the date by looking at https://static.rust-lang.org/manifests.txt and
-get the date of the most recent channel-rust-beta.toml.
+$STABLE is e.g. `1.80.0` (the stable release) and $BETA is `1.81.0-beta.1`. You can also pick a beta
+by date, example `beta-YYYY-MM-DD`, by looking at https://static.rust-lang.org/manifests.txt and get
+the date of the most recent channel-rust-beta.toml.
 
 ```console
 @craterbot run name=beta-$BETA_VERSION start=$STABLE end=$BETA mode=build-and-test cap-lints=warn p=10