Collect profiling information during SWA start-up and first request

[Mathos1432]

At the moment, the SWA-DAB has a cold start of around 30 secs. Collect profiling information to identify the areas where the most time is spent.

We need to wait for PerformOnConfigChangeAsync to complete before returning after the initial call.

We need to investigate improving the performance of this call to reduce latency on the initial request.

[Aniruddh25]

@severussundar, after profiling where time is spent the most at startup, we should figure out how we can improve performance of this function PerformOnConfigChangeAsync.

[Aniruddh25]

Using a huge config file for e.g. the reference config file here used for the integration testing, we see long delay(30s) when initializing SQL for the first time in the hosted solution. So, the performance we improve here should help solve this cold start problem.