Common custom fingerprint rules

### Problem Statement

I have several microservices on my project. All of them can face some specific network errors and I want these errors to be processed in the same way. In order to not mix these specific errors with other network errors, I need to add custom fingerprint rules. However, I have to add the same rule explicitly into each project in Sentry, which looks weird.

Need ability to specify custom fingerprint rules for multiple projects somehow.

### Solution Brainstorm

_No response_

### Product Area

Processing

Start with the issue's Processing area and the existing custom fingerprint rule configuration. Determine how rules could be scoped across multiple projects, then verify that the same rule is applied consistently without mixing these errors with other network errors.

Written by the indexing model from the issue text.