Resource detection for container properties in Flask

[sanketmehta28]

Problem
Detect the container id in Resource in flask framework

Describe the solution you'd like
Collect the container.id the application is running in and pass it as resource attribute in the tracer_provider

[srikanthccv]

This is not particularly related to Flask instrumentation. Flask instrumentation works with the tracer provided or obtained from the global provider. Hence closing. See my comment here #1372 (comment)