make sure curl fails on errors

provision/use-apt-repository.sh

@@ -23,6 +23,8 @@ popd
 # see https://help.sonatype.com/repomanager3/formats/apt-repositories
 apt-get install -y curl
 curl \
+    --fail \
+    --show-error \
     --user 'alice.doe:password' \
     --header 'Content-Type: multipart/form-data' \
     --data-binary @hello-world_1.0.0_amd64.deb \

provision/use-npm-repository.sh

@@ -13,7 +13,7 @@ mkdir -p tmp/use-npm-repository && cd tmp/use-npm-repository
 
 # install node LTS.
 # see https://github.com/nodesource/distributions#debinstall
-curl -sL https://deb.nodesource.com/setup_14.x | bash
+curl -sL --fail --show-error https://deb.nodesource.com/setup_14.x | bash
 apt-get install -y nodejs
 node --version
 npm --version

provision/use-raw-repository.sh

@@ -14,8 +14,8 @@ apt-get install -y curl
 # see https://help.sonatype.com/display/NXRM3/Raw+Repositories+and+Maven+Sites#RawRepositoriesandMavenSites-UploadingFilestoHostedRawRepositories
 expected='this is an adhoc package'
 echo "$expected" >package-1.0.0.txt
-curl --silent --user 'alice.doe:password' --upload-file package-1.0.0.txt https://$nexus_domain/repository/adhoc-package/package-1.0.0.txt
+curl --silent --fail --show-error --user 'alice.doe:password' --upload-file package-1.0.0.txt https://$nexus_domain/repository/adhoc-package/package-1.0.0.txt
 
 # download.
-actual=$(curl --silent https://$nexus_domain/repository/adhoc-package/package-1.0.0.txt)
+actual=$(curl --silent --fail --show-error https://$nexus_domain/repository/adhoc-package/package-1.0.0.txt)
 [ "$actual" = "$expected" ] || (echo 'upload adhoc package test failed' && false)