Nope. A law outlawing a certain practice is not a bill of attainder or ex post facto law, even if the law is designed only to apply to one person or entity. A bill of attainder declares a specific party guilty of a crime without trial. State legislatures have vast police powers, even when they use them in dumb partisan ways like they are in this case.
The clause thus prohibits all legislative acts, “no matter what their form, that apply either to named individuals or to easily ascertainable members of a group in such a way as to inflict punishment on them without a judicial trial. . . .”
(United States v. Lovett)