Fix travis script

Author: adimiz1

.travis.yml

@@ -1,18 +1,28 @@
 os:
   - linux
+dist: focal # Use Ubuntu Focal (20.04) for a more up-to-date environment
 sudo: false
+
 addons:
   apt:
     sources:
       - ubuntu-toolchain-r-test
     packages:
       - libstdc++6
       - fonts-droid-fallback
+
 before_script:
-  - git clone https://github.com/flutter/flutter.git -b beta
-  - ./flutter/bin/flutter doctor
+  # Clone the Flutter repository and ensure proper initialization
+  - git clone https://github.com/flutter/flutter.git -b stable # Use stable instead of beta for reliability
+  - export PATH="$PATH:`pwd`/flutter/bin" # Add Flutter to PATH
+  - flutter --version # Verify Flutter installation
+  - flutter precache # Precache necessary artifacts for the Flutter SDK
+  - flutter doctor # Verify the Flutter environment
+
 script:
-  - ./flutter/bin/flutter test
+  - flutter test # Run Flutter tests
+
 cache:
   directories:
-    - $HOME/.pub-cache
+    - $HOME/.pub-cache # Cache the pub packages
+    - flutter # Cache the Flutter SDK