fix download URL for DB 18.1.40

[boegel]

(created using eb --new-pr)

This only works for the latest release, auto-download for older releases is a lost cause it seems...

[boegel]

Test report by @boegel
SUCCESS
Build succeeded for 2 out of 2 (2 easyconfigs in total)
node2617.swalot.os - Linux centos linux 7.9.2009, x86_64, Intel(R) Xeon(R) CPU E5-2660 v3 @ 2.60GHz (haswell), Python 3.6.8
See https://gist.github.com/dfdc4fcedc1040f169291dccdbd32540 for a full test report.

[verdurin]

Test report by @verdurin
SUCCESS
Build succeeded for 2 out of 2 (2 easyconfigs in total)
easybuild-c7.novalocal - Linux centos linux 7.9.2009, x86_64, Intel Xeon Processor (Skylake, IBRS), Python 3.6.8
See https://gist.github.com/299dc323dd846062a625823c5c9530ef for a full test report.

[verdurin]

Test report by @verdurin
SUCCESS
Build succeeded for 2 out of 2 (2 easyconfigs in total)
nuc.lan - Linux Fedora 33, x86_64, Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz, Python 3.9.4
See https://gist.github.com/c98e43675c66a818da5b27e580a5cdfe for a full test report.

[verdurin]

Looks fine.

[verdurin]

Going in, thanks @boegel!