chore(turborepo): print the turbo version on start up (#8841)

### Description

I realized that we don't ever print the version of turborepo that's
running. This could be helpful for users and also for our testing.

### Testing Instructions

<!--
  Give a quick description of steps to test your changes.
-->

crates/turborepo-lib/src/cli/mod.rs

@@ -21,7 +21,7 @@ use turborepo_telemetry::{
     },
     init_telemetry, track_usage, TelemetryHandle,
 };
-use turborepo_ui::UI;
+use turborepo_ui::{GREY, UI};
 
 use crate::{
     cli::error::print_potential_tasks,
@@ -991,6 +991,13 @@ pub async fn run(
         }
     }
 
+    let should_print_version = env::var("TURBO_PRINT_VERSION_DISABLED")
+        .map_or(true, |disable| !matches!(disable.as_str(), "1" | "true"));
+
+    if should_print_version {
+        eprintln!("{}\n", GREY.apply_to(format!("turbo {}", get_version())));
+    }
+
     // If there is no command, we set the command to `Command::Run` with
     // `self.parsed_args.run_args` as arguments.
     let mut command = if let Some(command) = mem::take(&mut cli_args.command) {

turborepo-tests/helpers/setup.sh

@@ -13,4 +13,5 @@ fi
 export TURBO_TELEMETRY_MESSAGE_DISABLED=1
 export TURBO_GLOBAL_WARNING_DISABLED=1
 export TURBO_DOWNLOAD_LOCAL_ENABLED=0
+export TURBO_PRINT_VERSION_DISABLED=1
 TURBO=${MONOREPO_ROOT_DIR}/target/debug/turbo${EXT}

turborepo-tests/helpers/setup_integration_test.sh

@@ -37,6 +37,7 @@ fi
 
 export TURBO_TELEMETRY_MESSAGE_DISABLED=1
 export TURBO_GLOBAL_WARNING_DISABLED=1
+export TURBO_PRINT_VERSION_DISABLED=1
 export TURBO=${MONOREPO_ROOT_DIR}/target/debug/turbo${EXT}
 
 # Undo the set -eo pipefail at the top of this script