Bump demo apps to use lnc-rn to v0.3.1-alpha

[ViktorTigerstrom]

Based on #40

This PR updates our demo apps to solve previous build errors, and also to use lnc-rn v0.3.1-alpha.

Note that this PR is currently in draft mode as lnc-rn v0.3.1-alpha is not yet released, and therefore uses local linking to add that version. This PR can be used to test #40 until it has been released. I'll update this PR with using the actual lnc-rn v0.3.1-alpha link once it has been released.

[jamaljsr]

After spending many hours trying to get 830808b to work on android, I was not successful. I couldn't get past the Inconsistent JVM-target compatibility detected for tasks 'compileDebugJavaWithJavac' (11) and 'compileDebugKotlin' (17). error. I even started down the path of creating new demo apps, but aborted mission once I realized that I'd need to update some of the Kotlin and Objective-C code to make it compatible with the latest react-native. That was going to turn into a big project.

After pulling my hair out for quite a while, I decided to try to restart from cb7d304 just to see if the NPM dependencies could be the source of the issues. Shockingly, it worked immediately with no changes! 🤯

I'm honestly not sure how or why this happened. The only changes I made to my system was to upgrade Android Studio to the latest version and wiped these dirs.

cd demos/connect-demo/
rm -rf node_modules/ android/.gradle/ ~/.gradle/ ios/Pods/ ios/build/

Surprisingly, the connect-demo didn't work on iOS back on this commit for some reason. It was working when I tested last week. I had to change the iOS target for React-Codegen to 12.4. I was also running into this error below. I found a fix for it here that worked for me and could be added to this PR.

So now I have connect-demo working on both iOS and Android using cb7d304. I'll test out the multi-connect-demo on both tomorrow.

[ViktorTigerstrom]

Updated the PR to use the actual lnc-rn v0.3.1-alpha dependency that's now been released and removed the temp commits.

[jamaljsr]

utACK LGTM 🚀

Thanks for the updates.