util/docker: Remove manual symlink python3 to python

Debian sid symlinks already python3 to python.

Change-Id: Ibc3b2b047df7e1066624d4dd8aa9664ab1869222
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75875
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin L Roth <gaumless@gmail.com>
diff --git a/util/docker/coreboot-sdk/Dockerfile b/util/docker/coreboot-sdk/Dockerfile
index cca1b0a..3435b06 100644
--- a/util/docker/coreboot-sdk/Dockerfile
+++ b/util/docker/coreboot-sdk/Dockerfile
@@ -67,6 +67,7 @@
 		pbzip2 \
 		pkg-config \
 		python3 \
+		python-is-python3 \
 		qemu-system-arm \
 		qemu-system-misc \
 		qemu-system-ppc \
@@ -80,7 +81,6 @@
 		xz-utils \
 		zlib1g-dev \
 	&& apt-get clean \
-	&& update-alternatives --install /usr/bin/python python /usr/bin/python3 1 \
 	&& ln -s /usr/bin/automake /usr/bin/automake-1.15 \
 	&& ln -s /usr/bin/aclocal /usr/bin/aclocal-1.15