Increase build timeout to 55 minutes

This branch's test-with-cover seems to take a long time
so this commit increases the amount of time granted to it.

.travis.yml

@@ -4,7 +4,7 @@ go:
   - 1.13.x
 
 script:
-  - travis_wait 50 make test-with-cover
+  - travis_wait 60 make test-with-cover
 
 after_success:
   - bash <(curl -s https://codecov.io/bash)

make/test

@@ -19,7 +19,7 @@ default() {
 with-cover() {
   test -z "$(find . -path ./vendor -prune -type f -o -name '*.go' -exec gofmt -d {} + | tee /dev/stderr)"
   for d in $(go list ./... | grep -v '/vendor/' | grep -v '/hack'); do
-    go test -timeout 45m -json -v --race -coverprofile=profile.out -covermode=atomic $d | tparse
+    go test -timeout 55m -json -v --race -coverprofile=profile.out -covermode=atomic $d | tparse
     if [ -f profile.out ]; then
       cat profile.out >> coverage.txt
       rm profile.out