ESLint parity with the Browsertrix repo (#288)

This copies the rules from the Browsertrix repo, and uses
[`suppress-eslint-errors`](https://www.npmjs.com/package/suppress-eslint-errors)
to suppose the violations. I'll take a pass at cleaning this up at some
point in the future, and let's do our best to address these in the
future as we come across them :)

This'll help ensure new code being added to this repo is held to the
same standard as code in Browsertrix's frontend.

src/electron-preload.ts

@@ -17,11 +17,15 @@ async function getColl(name: string) {
     await dbs[name].initing;
   }
 
+  // TODO: Fix this the next time the file is edited.
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-return
   return dbs[name];
 }
 
 async function getDB(name: string) {
   const coll = await getColl(name);
+  // TODO: Fix this the next time the file is edited.
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-return
   return coll.store;
 }
 
@@ -43,6 +47,8 @@ async function getResponse(
     return;
   }
 
+  // TODO: Fix this the next time the file is edited.
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
   const headers = Object.fromEntries(result.headers.entries());
 
   const buffer = await result.getBuffer();