Revert "app-misc/ca-certificates: use github URLs"

This reverts commit 25de567365b64397fb9de6245ea80be005001768.

I think that the reverted commit was trying to fix a "non-error". On
Gentoo distfiles, it that seems a glitch has occured on
ca-certificates-3.120.1, as the decompressed archive tree files is not
consistent from one release to the other:
```
$ wget http://distfiles.gentoo.org/distfiles/37/nss-3.120.1.tar.gz
$ wget http://distfiles.gentoo.org/distfiles/43/nss-3.121.tar.gz
$ tar -xf nss-3.120.1.tar.gz
$ tar -xf nss-3.121.tar.gz
$ ls -l nss-3.121/nss
total 88
drwxr-xr-x  8 tormath1 tormath1   160 Mar  2 15:00 automation
-rwxr-xr-x  1 tormath1 tormath1  9183 Feb 19 10:30 build.sh
...
$ ls -l nss-NSS_3_120_1_RTM/
total 88
drwxr-xr-x  8 tormath1 tormath1   160 Feb 11 19:19 automation
-rwxr-xr-x  1 tormath1 tormath1  9183 Feb 11 19:19 build.sh
...

```

Signed-off-by: Mathieu Tortuyaux <mtortuyaux@microsoft.com>

sdk_container/src/third_party/coreos-overlay/app-misc/ca-certificates/ca-certificates-3.121.ebuild

@@ -9,11 +9,11 @@ inherit python-any-r1 systemd tmpfiles
 RTM_NAME="NSS_${PV//./_}_RTM"
 MY_PN="nss"
 MY_P="${MY_PN}-${PV}"
-S="${WORKDIR}/${MY_PN}-${RTM_NAME}"
+S="${WORKDIR}"
 
 DESCRIPTION="Mozilla's CA Certificate Store"
 HOMEPAGE="http://www.mozilla.org/en-US/about/governance/policies/security-group/certs/"
-SRC_URI="https://github.com/nss-dev/nss/archive/refs/tags/${RTM_NAME}.tar.gz -> ${MY_P}.tar.gz"
+SRC_URI="https://archive.mozilla.org/pub/security/nss/releases/${RTM_NAME}/src/${MY_P}.tar.gz"
 
 # NSS is licensed under the MPL, files/certdata2pem.py is GPL
 LICENSE="MPL-2.0 GPL-2"
@@ -68,7 +68,7 @@ gen_tmpfiles() {
 }
 
 src_compile() {
-	local certdata="${S}/lib/ckfw/builtins/certdata.txt"
+	local certdata="${MY_P}/nss/lib/ckfw/builtins/certdata.txt"
 	${PYTHON} "${FILESDIR}/certdata2pem.py" "${certdata}" certs || die
 
 	cd certs || die