.travis.yml: fix install of gcc-multilib (#29733)

Author: fjl

.travis.yml

@@ -56,14 +56,13 @@ jobs:
         - azure-linux
       git:
         submodules: false # avoid cloning ethereum/tests
-      addons:
-        apt:
-          packages:
-            - gcc-multilib
       script:
-        # Build for the primary platforms that Trusty can manage
+        # build amd64
         - go run build/ci.go install -dlgo
         - go run build/ci.go archive -type tar -signer LINUX_SIGNING_KEY -signify SIGNIFY_KEY -upload gethstore/builds
+
+        # build 386
+        - sudo -E apt-get install -yq --no-install-suggests --no-install-recommends --force-yes install gcc-multilib
         - go run build/ci.go install -dlgo -arch 386
         - go run build/ci.go archive -arch 386 -type tar -signer LINUX_SIGNING_KEY -signify SIGNIFY_KEY -upload gethstore/builds
 
@@ -165,4 +164,3 @@ jobs:
       go: 1.22.x
       script:
         - travis_wait 30 go run build/ci.go test  -race $TEST_PACKAGES
-