[Event Hubs] Update package.json files to have sideEffects set to false

[ramya-rao-a]

As per the Typescript guidelines, we need to set sideEffects to false in the package.json files.

Relevant section from the guidelines

DO set sideEffects to false. Side effecting libraries must be explicitly approved during design review. The sideEffects field is used by Webpack and potentially other tools as an indicator of how aggressively the package can be optimized.

Side effects refer to modifications to the runtime environment of the program as a result of including a module. For example, including a polyfill library is a sideEffect as it mutates the global environment and later code depends on its presence. Side effects make it harder for tools to optimize your build and should be avoided

This issue is to track the required update in both EPH and Event Hubs

[ShivangiReja]

Closed with #2767