Fix no default imports

[g-ongenae]

The current default imports throw those errors:

node_modules/ical-generator/index.d.ts(5,10): error TS1192: Module '"/usr/src/app/node_modules/moment/moment"' has no default export.
node_modules/ical-generator/index.d.ts(6,10): error TS1192: Module '"http"' has no default export.

[g-ongenae]

Fix it with the use of allowSyntheticDefaultImports option.
See microsoft/TypeScript#3337 (comment)

[evelynhathaway]

Actually, that's a good point. I have "esModuleInterop": true on in my tsconfig.json and esModuleInterop implicitly adds allowSyntheticDefaultImports (TIL) which is why I missed those errors while I was converting to default imports as VSCode suggested.

So, I'll create another PR co-authoring with you to explicitly collect the entire module into their bindings.