fix(windows): avoid inadvertly running exes from cwd (#2885)

On Windows when running commands with their name instead of the path with Command::new, executable with that name from the current working directory will be executed.

This PR replaces all instances of Command::new with a new create_command function which will first resolve any executable paths and avoid this issue.

src/bug_report.rs

@@ -265,18 +265,6 @@ mod tests {
         assert!(link.contains("No+Starship+config"));
     }
 
-    #[test]
-    fn test_get_shell_info() {
-        env::remove_var("STARSHIP_SHELL");
-        let unknown_shell = get_shell_info();
-        assert_eq!(UNKNOWN_SHELL, &unknown_shell.name);
-
-        env::set_var("STARSHIP_SHELL", "fish");
-
-        let fish_shell = get_shell_info();
-        assert_eq!("fish", &fish_shell.name);
-    }
-
     #[test]
     #[cfg(not(windows))]
     fn test_get_config_path() {