[minimega] fix bridge variable so deleting netflow capture works

[activeshadow]

When deleting a netflow capture, the bridge name was getting assigned to the <name> variable but the code that deletes the capture was trying to get the name of the bridge from the <bridge> variable.

[activeshadow]

@jacdavi can you merge this in since it's been approved?

[jacdavi]

oh yeah sorry. I was wrapping up some release stuff, so I only approved it before, but that's all taken care of now.