I am having this issue too. Alfred relaunches after a couple seconds.
As advised, I've checked ~/Library/LaunchAgents. There, there is a file ~/Library/LaunchAgents/com.alfredapp.1password.plist containing the following code
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>com.alfredapp.1password</string>
<key>ProgramArguments</key>
<array>
<string>/usr/bin/osascript</string>
<string>-e</string>
<string>if application id "com.runningwithcrayons.Alfred" is running then tell application id "com.runningwithcrayons.Alfred" to run trigger "data_update_detected" in workflow "com.alfredapp.1password"</string>
</array>
<key>WatchPaths</key>
<array>
<string>~/Library/Group Containers/2BUA8C4S2C.com.1password/Library/Application Support/1Password/Data</string>
</array>
</dict>
</plist>
If I delete it, it does not stop the issue, and seems to be recreated every time Alfred relaunches automatically.
This is super annoying, so please help!