Update Samples for 3.16 (#2085)

*Replace this paragraph with a description of what this PR is changing
or adding, and why. Consider including before/after screenshots.*

*List which issues are fixed by this PR. For larger changes, raising an
issue first helps
reduce redundant work.*

## Pre-launch Checklist

- [ ] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [ ] I signed the [CLA].
- [ ] I read the [Contributors Guide].
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-devrel
channel on [Discord].

<!-- Links -->
[Flutter Style Guide]:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[CLA]: https://cla.developers.google.com/
[Discord]: https://github.com/flutter/flutter/wiki/Chat
[Contributors Guide]:
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provider_shopper/android/build.gradle

@@ -6,7 +6,6 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:7.3.0'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }

provider_shopper/android/gradle.properties

@@ -1,3 +1,3 @@
-org.gradle.jvmargs=-Xmx1536M
+org.gradle.jvmargs=-Xmx4G
 android.useAndroidX=true
 android.enableJetifier=true

provider_shopper/android/settings.gradle

@@ -10,11 +10,20 @@ pluginManagement {
 
     includeBuild("${settings.ext.flutterSdkPath}/packages/flutter_tools/gradle")
 
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
+
     plugins {
         id "dev.flutter.flutter-gradle-plugin" version "1.0.0" apply false
     }
 }
 
-include ":app"
+plugins {
+    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
+    id "com.android.application" version "7.3.0" apply false
+}
 
-apply from: "${settings.ext.flutterSdkPath}/packages/flutter_tools/gradle/app_plugin_loader.gradle"
+include ":app"