Examples: Add an example which uses a resource bundle

[euanh]

Motivation

An example showing how to use resources (#78) is helpful for new users and can be used as an end to end tests for this feature.

Modifications

• Add a new HelloWorldWithResources example
• Add the new example to the End to end tests GitHub Actions job
• Restructure the end to end tests to check the HTTP response code instead of the content which is returned, because the new test returns one of 3 JPEGs selected at random, whereas the existing tests returned strings.
• Adopt the code structure used by the official Hummingbird examples, to make it more familiar to users who are used to the official examples.

Result

• The repository contains a new example showing how to use resources in a container image
• The resource feature is tested as part of the automated end to end test suite.

Test Plan

The new test passes and all existing tests continue to pass.