action: get latest tag by Github API

Use https://api.github.com/repos/Dragonflyoss/nydus/releases/latest to get the
latest tag of nydus, and used in smoke/integration-test.

Signed-off-by: Yadong Ding <ding_yadong@foxmail.com>

.github/workflows/smoke.yml

@@ -16,8 +16,6 @@ env:
   CARGO_TERM_COLOR: always
   IMAGE: wordpress
   TAG: 6.1.1
-  NYDUS_STABLE_VERSION: v2.2.3
-  NYDUS_STABLE_VERSION_EXPORT: v2_2_3
 
 jobs:
   contrib-build:
@@ -151,8 +149,10 @@ jobs:
     - name: Prepare Older Binaries
       id: prepare-binaries
       run: |
-        versions=(v0.1.0 ${{env.NYDUS_STABLE_VERSION}})
-        version_archs=(v0.1.0-x86_64 ${{env.NYDUS_STABLE_VERSION}}-linux-amd64)
+        export NYDUS_STABLE_VERSION=$(curl https://api.github.com/repos/Dragonflyoss/nydus/releases/latest | jq -r '.tag_name')
+
+        versions=(v0.1.0 ${NYDUS_STABLE_VERSION})
+        version_archs=(v0.1.0-x86_64 ${NYDUS_STABLE_VERSION}-linux-amd64)
         for i in ${!versions[@]}; do
           version=${versions[$i]}
           version_arch=${version_archs[$i]}
@@ -177,8 +177,11 @@ jobs:
         sudo install -D -m 755 contrib/nydusify/cmd/nydusify /usr/bin/nydus-latest
         sudo install -D -m 755 target/release/nydusd target/release/nydus-image /usr/bin/nydus-latest
 
-        versions=(v0.1.0 ${{env.NYDUS_STABLE_VERSION}} latest)
-        version_exports=(v0_1_0 ${{env.NYDUS_STABLE_VERSION_EXPORT}} latest)
+        export NYDUS_STABLE_VERSION=$(curl https://api.github.com/repos/Dragonflyoss/nydus/releases/latest | jq -r '.tag_name')
+        export NYDUS_STABLE_VERSION_EXPORT="${NYDUS_STABLE_VERSION//./_}"
+
+        versions=(v0.1.0 ${NYDUS_STABLE_VERSION} latest)
+        version_exports=(v0_1_0 ${NYDUS_STABLE_VERSION_EXPORT} latest)
         for i in ${!version_exports[@]}; do
           version=${versions[$i]}
           version_export=${version_exports[$i]}