fixes manifest tool to a stable version

Author: jaymoulin

.travis.yml

@@ -5,7 +5,7 @@ services:
 
 before_install:
     - sudo apt update && sudo apt install make -y
-    - git clone https://github.com/estesp/manifest-tool && cd manifest-tool && sudo make && sudo make install && cd .. && rm -Rf manifest-tool
+    - git clone https://github.com/estesp/manifest-tool && cd manifest-tool && git checkout v0.9.0 && sudo make && sudo make install && cd .. && rm -Rf manifest-tool
     - docker run --rm --privileged multiarch/qemu-user-static:register
     - sudo apt install -y qemu qemu-user-static qemu-user binfmt-support