Pub enum runtime to pub struct runtime (#13250)

* pub enum Runtime -> pub struct Runtime

* changing some more

* fmt

* updating *.stderr files

* re-run trybuild after rust update

* keep a test file for `pub enum Runtime`

* Delete construct_runtime_2.rs

* ".git/.scripts/commands/fmt/fmt.sh"

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Co-authored-by: Bastian Köcher <[email protected]>
Co-authored-by: parity-processbot <>