Colin Kaepernick Teams with Usher to Complete $1 Million Pledge

[[tmz:video id="0_muu2n5ph"]] Colin Kaepernick just wrote his LAST check as part of his "$1 Million Pledge" campaign -- and teamed up with Usher to end it with a bang. Remember, Kaep first started the program back in 2016 ... vowing to donate $1…