LexBash: Don't allow spaces between `<<` and `-` in a heredoc operator
LexBash: Don't allow spaces between `<<` and `-` in a heredoc operator

`<<-` is an operator of itself, not two separate tokens `<<` and `-`.
This fixes handling of delimiters starting with `-`, like this:

    cat<< -EOF
    ...
    -EOF

timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla,timonwong/foo_uie_wsh_panel_mod.scintilla