git-review: 1.25.0 -> 1.26.0

Semi-automatic update. These checks were done:

- built on NixOS
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/.git-review-wrapped -h` got 0 exit code
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/.git-review-wrapped --help` got 0 exit code
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/.git-review-wrapped --version` and found version 1.26.0
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/git-review -h` got 0 exit code
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/git-review --help` got 0 exit code
- ran `/nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0/bin/git-review --version` and found version 1.26.0
- found 1.26.0 with grep in /nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0
- found 1.26.0 in filename of file in /nix/store/p5k6zxrdcnl84xjnkicm3wblq20c82l5-git-review-1.26.0