Change repository URLs to https

HTTPS updates works more reliably over Tor. But also provide some
additional privacy.

Fixes QubesOS/qubes-issues#3737

misc/qubes-r4.repo

@@ -1,6 +1,6 @@
 [qubes-vm-r4.0-current]
 name = Qubes OS Repository for VM (updates)
-baseurl = http://yum.qubes-os.org/r4.0/current/vm/fc$releasever
+baseurl = https://yum.qubes-os.org/r4.0/current/vm/fc$releasever
 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-qubes-4-primary
 skip_if_unavailable=False
 gpgcheck = 1
@@ -8,7 +8,7 @@ enabled=1
 
 [qubes-vm-r4.0-current-testing]
 name = Qubes OS Repository for VM (updates-testing)
-baseurl = http://yum.qubes-os.org/r4.0/current-testing/vm/fc$releasever
+baseurl = https://yum.qubes-os.org/r4.0/current-testing/vm/fc$releasever
 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-qubes-4-primary
 skip_if_unavailable=False
 gpgcheck = 1
@@ -16,7 +16,7 @@ enabled=0
 
 [qubes-vm-r4.0-security-testing]
 name = Qubes OS Repository for VM (security-testing)
-baseurl = http://yum.qubes-os.org/r4.0/security-testing/vm/fc$releasever
+baseurl = https://yum.qubes-os.org/r4.0/security-testing/vm/fc$releasever
 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-qubes-4-primary
 skip_if_unavailable=False
 gpgcheck = 1
@@ -24,7 +24,7 @@ enabled=0
 
 [qubes-vm-r4.0-unstable]
 name = Qubes OS Repository for VM (unstable)
-baseurl = http://yum.qubes-os.org/r4.0/unstable/vm/fc$releasever
+baseurl = https://yum.qubes-os.org/r4.0/unstable/vm/fc$releasever
 gpgkey = file:///etc/pki/rpm-gpg/RPM-GPG-KEY-qubes-4-unstable
 gpgcheck = 1
 enabled=0