Deploying with a blank file ends in a terrible error

[lastmjs]

We should create a pretty error or no error for deploying a canister with an empty main file, but we currently get this:

Azle BuildError: Error: Error: cannot set property '_azleShouldRegisterCanisterMethods' of undefined
    at getExportedCanisterClassInstance (.azle/agent/main.js:4957:5)
    at <anonymous> (.azle/agent/main.js:4930:37)

    at trap (/home/lastmjs/development/azle/src/build/stable/commands/compile/candid_and_method_meta/execute.ts:76:23)
    at wasm://wasm/00c98e8a:wasm-function[2915]:0x2138f4
    at wasm://wasm/00c98e8a:wasm-function[1079]:0x1b2938
    at wasm://wasm/00c98e8a:wasm-function[90]:0x7d0ba
    at wasm://wasm/00c98e8a:wasm-function[3244]:0x214f5e
    at execute (/home/lastmjs/development/azle/src/build/stable/commands/compile/candid_and_method_meta/execute.ts:95:7)
    at handleAutomaticAndCustom (/home/lastmjs/development/azle/src/build/stable/commands/compile/candid_and_method_meta/index.ts:45:42)
    at async getCandidAndMethodMeta (/home/lastmjs/development/azle/src/build/stable/commands/compile/candid_and_method_meta/index.ts:20:16)
    at async runCommand (/home/lastmjs/development/azle/src/build/stable/commands/compile/index.ts:26:36)
    at async handleCompileCommand (/home/lastmjs/development/azle/src/build/index.ts:151:9)