fix libPapiQuickjs.so import settings for Android (#2361)

The Android plugin import settings for libPapiQuickjs.so are wrong in two of
the three ABIs, and the result is that the QuickJS backend cannot be loaded on
a real device:

- arm64-v8a has no Android platform entry at all, so the library is not
  packaged into the APK. This is the ABI essentially every current Android
  device runs.
- armeabi-v7a declares CPU: ARM64. Two of the three ABIs therefore claim
  arm64 and none claims ARMv7.

The build succeeds either way, and the app then fails at the first script
with:

  DllNotFoundException: Unable to load DLL 'PapiQuickjs'
    dlerror() = dlopen failed: library "PapiQuickjs" not found
    at Puerts.ScriptEnv..ctor

libPuertsCore.so.meta in unity/upms/core is correct for all three ABIs, so
this makes the quickjs ones match it: arm64-v8a -> ARM64, armeabi-v7a ->
ARMv7, x86_64 -> X86_64 (already correct). After this change the three
libPapiQuickjs.so.meta files are identical to the corresponding
libPuertsCore.so.meta files apart from the guid.

Nothing in the editor catches this, because no editor test loads the Android
native libraries.

Author: chagretes