Syncthing-Fork: fix 0.14.50.rc2.6 (4154)

Go 1.9 is not available in the testing anymore.

metadata/com.github.catfriend1.syncthingandroid.yml

@@ -48,18 +48,18 @@ Builds:
     versionCode: 4154
     commit: v0.14.50.rc2.6
     submodules: true
-    sudo: |-
-        apt-get install -y golang-1.9-go/testing
-        ln -s /usr/lib/go-1.9/bin/go /usr/bin/go
     gradle:
       - yes
     output: app/build/outputs/apk/release/app-release-unsigned.apk
     rm:
       - syncthing/src/github.com/syncthing/syncthing/lib/model/testdata
     prebuild: sed -i -e '/signingConfig/d' app/build.gradle
+    build: |-
+        wget -O go.tgz https://dl.google.com/go/go1.9.7.linux-amd64.tar.gz && \
+        echo '88573008f4f6233b81f81d8ccf92234b4f67238df0f0ab173d75a302a1f3d6ee  go.tgz' | shasum -c - && \
+        tar xf go.tgz && \
+        PATH="$PWD/go/bin:$PATH" gradle buildNative
     ndk: r15c
-    preassemble:
-      - buildNative
 
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