Release 1.2.1

- Fixed the dictionary update card taking too long to reappear after
  cancelling a download (DownloadManager).
- Bump agp 9.3.0 -> 9.3.1; migrate the release build type from
  isMinifyEnabled/isShrinkResources/proguardFiles to
  optimization { enable = true } with keep rules moved to
  app/src/release/keepRules/proguard-rules.keep.

app/build.gradle.kts

@@ -92,8 +92,8 @@ android {
         applicationId = "com.example.research"
         minSdk = project.property("minSdk").toString().toInt()
         targetSdk = project.property("targetSdk").toString().toInt()
-        versionCode = 4
-        versionName = "1.2.0"
+        versionCode = 5
+        versionName = "1.2.1"
 
         vectorDrawables {
             useSupportLibrary = true
@@ -114,12 +114,9 @@ android {
                 abiFilters += "arm64-v8a"
             }
 
-            isMinifyEnabled = true
-            isShrinkResources = true
-            proguardFiles(
-                getDefaultProguardFile("proguard-android-optimize.txt"),
-                "proguard-rules.pro"
-            )
+            optimization {
+                enable = true
+            }
         }
 
     }