Revert "temporary fix: sourced .bashrc to set $PATH"

This reverts commit 072b942b1e.

src/main.rs

@@ -149,10 +149,7 @@ fn run(
     log.write(format!("CI run spec: {:#?}\n", runspec))?;
 
     debug!("running CI in cloned repository");
-    let snippet = format!(
-        "set -xeuo pipefail\nsource $HOME/.bashrc\n\n{}",
-        &runspec.shell
-    );
+    let snippet = format!("set -xeuo pipefail\n{}", &runspec.shell);
     runcmd(&mut run_log, &["bash", "-c", &snippet], src)?;
 
     write_response(&Response::finished(RunResult::Success))?;