Update vite integration instructions with proper tsconfig include

[youssefm]

This is a simple documentation update.

The current tsconfig provided in the docs does not work at all. This updates the docs to include any ts file within the src directory.

[janechu]

Updated for future docs release for v2 of @microsoft/fast-element per this PRs change see https://github.com/microsoft/fast/commit/10e74063b358cdf36ba86e5f38cffdc2617ee5c7