[move core modules] Remove AccountRecovery.md documentation
[move core modules] Remove AccountRecovery.md documentation

This doc file was added in PR #4342 without any corresponding module.
Presumably it was renamed to RecoveryAccount and the generated doc
file with the earlier name was not removed.

Closes: #4362
Approved by: sblackshear

libra/libra,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,libra/libra,aptos-labs/aptos-core