chore: pinned minifying library version

We've had problems with this before, and I want to make sure it can't
bite us before we go stable.

Author: arctic-hen7

packages/perseus/Cargo.toml

@@ -35,7 +35,8 @@ fs_extra = "1"
 http = "0.2"
 urlencoding = "2.1"
 chrono = "0.4"
-minify-html-onepass = "0.10.1"
+# Be very careful about changing this! Patches may be required in Perseus.
+minify-html-onepass = "=0.10.1"
 
 # These dependencies will also be available in documentation
 [target.'cfg(any(client, clientdoc))'.dependencies]