docs: Infer version of patched Conan dependency to export

[bthomee]

High Level Overview of Change

This change updates a script in the documentation to automatically infer the version of a patched Conan dependency from the conan.lock file.

Context of Change

To avoid keeping version numbers in sync across multiple locations, we can relatively easily extract the version number of a dependency we patched in our own Conan Center Index fork by parsing the lock file.

This change is using sed to do the extraction, as the command will work on both Linux and macOS. In contrast, for grep the oP flag is needed, which isn't available on macOS; this can be remedied by running brew install grep and then also modifying the command to use ggrep instead; this is a lot of effort. Naturally, other solutions exist too, but sed seemed simplest for this purpose.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (non-breaking change that only restructures code)
• Performance (increase or change in throughput and/or latency)
• Tests (you added tests for code that already exists, or your new feature included in this PR)
• Documentation update
• Chore (no impact to binary, e.g. .gitignore, formatting, dropping support for older tooling)
• Release

[pratikmankawde]

Looks good