examples/android: specify the exact NDK (r25c) version to use

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4747>

subprojects/gst-docs/examples/tutorials/android/android-tutorial-1/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+    ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-docs/examples/tutorials/android/android-tutorial-2/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-docs/examples/tutorials/android/android-tutorial-3/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-docs/examples/tutorials/android/android-tutorial-4/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-docs/examples/tutorials/android/android-tutorial-5/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-examples/playback/player/android/app/build.gradle

@@ -45,6 +45,7 @@ android {
             path 'src/main/jni/Android.mk'
         }
     }
+    ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-examples/vulkan/android/build.gradle

@@ -56,6 +56,7 @@ android {
             path 'jni/Android.mk'
         }
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {

subprojects/gst-examples/webrtc/android/app/build.gradle

@@ -49,6 +49,7 @@ android {
     lintOptions {
         abortOnError false
     }
+  ndkVersion '25.2.9519653'
 }
 
 afterEvaluate {