module no longer avoided as a variable name

[Conduitry]

• Rollup Version: 1.13.0
• Operating System (or Browser): Linux
• Node Version: 12.3.1

How Do We Reproduce?

Between 1.12.5 and 1.13.0, module stopped being avoided as a variable name. Compare this REPL and this one. The code produced in the REPL doesn't cause an error in Node, but if you bundle with preferConst: true, it results in const module = 42;, which Node does complain about as being a variable getting redeclared.

Expected Behavior

module should continue to be deconflicted from the Node built-in, at least in preferConst mode.

Actual Behavior

Rollup will output code like const module = 42;, which Node doesn't like.

[lukastaegert]

Thanks for spotting this, proper fix at #2889