Fix Ollama update logic (#3506)

Author: tremor021

ct/openwebui.sh

@@ -28,11 +28,11 @@ function update_script() {
     exit
   fi
 
-  OLLAMA_VERSION=$(ollama -v | awk '{print $NF}')
-  if [ -n "$OLLAMA_VERSION" ]; then
-    RELEASE=$(curl -s https://api.github.com/repos/ollama/ollama/releases/latest | grep "tag_name" | awk '{print substr($2, 3, length($2)-4) }')
+  if [ -x "/usr/bin/ollama" ]; then
+    msg_info "Updating Ollama"
+    OLLAMA_VERSION=$(ollama -v | awk '{print $NF}')
+    RELEASE=$(curl -s https://api.github.com/repos/ollama/ollama/releases/latest | grep "tag_name" | awk '{print substr($2, 3, length($2)-4)}')
     if [ "$OLLAMA_VERSION" != "$RELEASE" ]; then
-      msg_info "Updating Ollama"
       curl -fsSLO https://ollama.com/download/ollama-linux-amd64.tgz
       tar -C /usr -xzf ollama-linux-amd64.tgz
       rm -rf ollama-linux-amd64.tgz