package/monit: fix URL in hash file comment

package/monit: fix URL in hash file comment

Previous URL gives:

    % curl https://mmonit.com/monit/dist/monit-5.25.3.tar.gz.sha256
    c10258c8839d20864d30390e7cbf2ff5e0480a67a6fb80c02aa457d6e3390569 monit-5.25.3.tar.gz

Current URL is:

    % curl https://mmonit.com/monit/dist/monit-5.26.0.tar.gz.sha256
    87fc4568a3af9a2be89040efb169e3a2e47b262f99e78d5ddde99dd89f02f3c2 monit-5.26.0.tar.gz

This was probably just forgotten on the last version bump.

Fixes: ad250c3d1884 ("package/monit: bump to version 5.26.0")
Signed-off-by: Alexander Dahl <post@lespocky.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>