[dev-infra] Removing pre-command from install_pkg invocation
[dev-infra] Removing pre-command from install_pkg invocation

install_pkg is a shell function, and if the pre-command e.g. expands to `sudo` like in my ubuntu system, this leads to failure.

Closes: #8577

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