[Feature Request] Add support for reporting with pprof's profile.proto format in CLI tools

## Background and Motivation

Pprof's profile.proto format is a generic format for profiling output. Adding support for this format would allow us to use existing tools to generate flamegraph visualizations and perform data analysis. More info: https://github.com/google/pprof/tree/master/proto

## Proposed Feature

Add the option to format output in gzipped profile.proto format in tools like dotnet-gcdump, dotnet-stack, etc.

For dotnet-stack, the output sample stack should consist of the stack trace of each thread, with one measurement (count).
For dotnet-gcdump, the sample stack should consist of parent objects and their associated child objects with two measurements (count and size).
For dotnet-trace, the sample stack should consist of the stack trace of each event, with two measurements (duration and sample count).

## Usage Examples

```
dotnet-gcdump report --format proto
dotnet-stack report --format proto
dotnet-trace collect --format proto
```