fix(bashrc): use `-r` instead of `-f` for condition evaluation
fix(bashrc): use `-r` instead of `-f` for condition evaluation

Type `man [` to see the meaning of the flags:

-f file       True if file exists and is a regular file.
-r file       True if file exists and is readable.

shoichiaizawa/dotfiles,shoichiaizawa/dotfiles,shoichiaizawa/dotfiles