Rename 3512 script to make it all lowercase.

BUG=b/325443957
TEST=None
RELEASE_NOTE=None

cos-patch: bug
Change-Id: I9c4260de6328a85b2e6c4c5df15377ff8ff6774e

alphabet-compliance/scripts/3512-configure-ipv6-loopback.sh

diff --git a/alphabet-compliance/scripts/3512-configure-IPv6-loopback.sh b/alphabet-compliance/scripts/3512-configure-ipv6-loopback.sh
similarity index 100%
rename from alphabet-compliance/scripts/3512-configure-IPv6-loopback.sh
rename to alphabet-compliance/scripts/3512-configure-ipv6-loopback.sh