deprecate `try-runtime` subcommand and direct users to standalone cli

[liamaharon]

Partial https://github.com/paritytech/substrate/issues/12975

The try-runtime subcommand has been migrated to a standalone CLI: https://github.com/paritytech/try-runtime-cli/pull/6

Removing the tests at the same time because to reduce load on the CI, they take a long time to run. Tests are migrated to the new repo.

polkadot companion: https://github.com/paritytech/polkadot/pull/7599

TODO before merge

• [x] Remove --branch liam-v0.1.0 from CI command once https://github.com/paritytech/try-runtime-cli/pull/6 is merged.

[liamaharon]

bot merge

[paritytech-processbot[bot]]

Error: Statuses failed for b550ff411d7aa02a55f0ff1c1f5dda30dd224518

[liamaharon]

bot merge force