[Fleet] Fix download URL for Agent Standalone (#217468)

## Summary

Closes https://github.com/elastic/elastic-agent/issues/7716

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support](https://github.com/elastic/kibana/blob/main/src/platform/packages/shared/kbn-i18n/README.md)
- [ ]
[Documentation](https://www.elastic.co/guide/en/kibana/master/development-documentation.html)
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were updated or added to match the most common scenarios
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- [ ] ...

x-pack/plugins/fleet/public/components/enrollment_instructions/standalone/index.tsx

@@ -22,24 +22,24 @@ export const StandaloneInstructions = ({
   const { windows: windowsDownloadSourceProxyArgs, curl: curlDownloadSourceProxyArgs } =
     getDownloadSourceProxyArgs(downloadSourceProxy);
 
-  const linuxDebCommand = `curl -L -O ${downloadBaseUrl}/downloads/beats/elastic-agent/elastic-agent-${agentVersion}-amd64.deb ${curlDownloadSourceProxyArgs}
+  const linuxDebCommand = `curl -L -O ${downloadBaseUrl}/beats/elastic-agent/elastic-agent-${agentVersion}-amd64.deb ${curlDownloadSourceProxyArgs}
 sudo dpkg -i elastic-agent-${agentVersion}-amd64.deb \nsudo systemctl enable elastic-agent \nsudo systemctl start elastic-agent`;
 
-  const linuxRpmCommand = `curl -L -O ${downloadBaseUrl}/downloads/beats/elastic-agent/elastic-agent-${agentVersion}-x86_64.rpm ${curlDownloadSourceProxyArgs}
+  const linuxRpmCommand = `curl -L -O ${downloadBaseUrl}/beats/elastic-agent/elastic-agent-${agentVersion}-x86_64.rpm ${curlDownloadSourceProxyArgs}
 sudo rpm -vi elastic-agent-${agentVersion}-x86_64.rpm \nsudo systemctl enable elastic-agent \nsudo systemctl start elastic-agent`;
 
-  const linuxCommand = `curl -L -O ${downloadBaseUrl}/downloads/beats/elastic-agent/elastic-agent-${agentVersion}-linux-x86_64.tar.gz ${curlDownloadSourceProxyArgs}
+  const linuxCommand = `curl -L -O ${downloadBaseUrl}/beats/elastic-agent/elastic-agent-${agentVersion}-linux-x86_64.tar.gz ${curlDownloadSourceProxyArgs}
 tar xzvf elastic-agent-${agentVersion}-linux-x86_64.tar.gz
 cd elastic-agent-${agentVersion}-linux-x86_64
 sudo ./elastic-agent install`;
 
-  const macCommand = `curl -L -O ${downloadBaseUrl}/downloads/beats/elastic-agent/elastic-agent-${agentVersion}-darwin-aarch64.tar.gz ${curlDownloadSourceProxyArgs}
+  const macCommand = `curl -L -O ${downloadBaseUrl}/beats/elastic-agent/elastic-agent-${agentVersion}-darwin-aarch64.tar.gz ${curlDownloadSourceProxyArgs}
 tar xzvf elastic-agent-${agentVersion}-darwin-aarch64.tar.gz
 cd elastic-agent-${agentVersion}-darwin-aarch64
 sudo ./elastic-agent install`;
 
   const windowsCommand = `$ProgressPreference = 'SilentlyContinue'
-Invoke-WebRequest -Uri ${downloadBaseUrl}/downloads/beats/elastic-agent/elastic-agent-${agentVersion}-windows-x86_64.zip -OutFile elastic-agent-${agentVersion}-windows-x86_64.zip ${windowsDownloadSourceProxyArgs}
+Invoke-WebRequest -Uri ${downloadBaseUrl}/beats/elastic-agent/elastic-agent-${agentVersion}-windows-x86_64.zip -OutFile elastic-agent-${agentVersion}-windows-x86_64.zip ${windowsDownloadSourceProxyArgs}
 Expand-Archive .\elastic-agent-${agentVersion}-windows-x86_64.zip -DestinationPath .
 cd elastic-agent-${agentVersion}-windows-x86_64
 .\\elastic-agent.exe install`;