Zap tries to zap d.ts files

[lucacasonato]

// style.js
/// <reference types="./style.d.ts" />
export const CSS = "";

// style.d.ts
export const CSS: string;

TS1039 [ERROR]: Initializers are not allowed in ambient contexts.
export const CSS: string = {} as any;
                           ~~~~~~~~~
    at file:///Users/lucacasonato/projects/github.com/lucacasonato/deno-gfm/style.d.ts:1:25

[dsherret]

Excellent--type checking step catching bugs.

By the way, zap should still zap dts files, but just not add expressions to the file.