Use fewer type assertions

For example,

```typescript
// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
const d = new Date(value as number | string | Date);
```

can _probably_ become:

```typescript
const d = new Date(typeof value === "string" ? value : +value);
```

(courtesy of:)

```typescript
/**
* Converts a Date object to a number.
*/
[Symbol.toPrimitive](hint: "number"): number;
```