chore: Update docs about dropping the support for RN 0.79 since 4.19.0 (#3457)

## Description

According to the policy of supporting 3 past versions of React Native,
I'm adding a note that starting from `[email protected]`, we
are dropping support for `[email protected]`. I reviewed the code and
did not find any specific version checks related to 0.79 that we need to
remove (I only checked for 0.79, not earlier versions).

Fixes
software-mansion/react-native-screens-labs#702

## Changes

- Updated `README.md` docs

## Test code and steps to reproduce

N/A

## Checklist

- [x] Included code example that can be used to test this change
- [x] Ensured that CI passes

Author: t0maboro

README.md

@@ -121,6 +121,7 @@ Here's a table with summary of supported `react-native` versions:
 
 | library version | react-native version |
 | --------------- | -------------------- |
+| 4.19.0+         | 0.81.0+              |
 | 4.14.0+         | 0.79.0+              |
 | 4.5.0+          | 0.77.0+              |
 | 4.0.0+          | 0.76.0+              |
@@ -133,6 +134,7 @@ Here's a table with summary of supported `react-native` versions with old archit
 
 | library version | react-native version |
 | --------------- | -------------------- |
+| 4.19.0+         | 0.80.0+              |
 | 4.14.0+         | 0.79.0+              |
 | 4.9.0+          | 0.76.0+              |
 | 4.5.0+          | 0.74.0+              |