TOOL-30021 Enable upstream tracking for sdb against sdimitro/sdb develop

Wire packages/sdb/config.sh up to the upstream-tracking automation
introduced by the prior commit, completing Phase 2 of
delphix/cd-aidlc spec 0003 (Adopt sdimitro/sdb as upstream;
repackage via dh-virtualenv).

The build() override derives PACKAGE_VERSION from setuptools_scm so
the .deb's metadata version follows upstream sdb tags automatically;
pyproject.toml's local_scheme="no-local-version" keeps the value
debian-version-safe (no embedded "-"), letting linux-pkg's
set_changelog append the standard "-1delphix.<ts>" revision suffix
without further massaging.

Phase 1 (delphix/sdb#360, merged 2026-05-06) landed the bootstrap
merge from sdimitro/develop plus the dh-virtualenv overlay,
including python3-setuptools-scm in Build-Depends so the build()
override here works with no companion delphix/sdb change.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: prakashsurya

packages/sdb/config.sh

@@ -18,10 +18,27 @@
 # shellcheck disable=SC2034
 DEFAULT_PACKAGE_GIT_URL="https://github.com/delphix/sdb.git"
 
+UPSTREAM_GIT_URL="https://github.com/sdimitro/sdb.git"
+UPSTREAM_GIT_BRANCH="develop"
+
 function prepare() {
 	logmust install_build_deps_from_control_file
 }
 
 function build() {
+	local scm_version
+	scm_version=$(cd "$WORKDIR/repo" && python3 -m setuptools_scm 2>/dev/null) \
+		|| die "setuptools_scm version derivation failed"
+	#
+	# pyproject.toml sets local_scheme="no-local-version", so the value
+	# is debian-version-safe. Pass it through as-is; linux-pkg's
+	# set_changelog appends "-1delphix.<ts>" since PACKAGE_VERSION has
+	# no "-", producing e.g. "0.6.0-1delphix.<ts>".
+	#
+	export PACKAGE_VERSION="${scm_version}"
 	logmust dpkg_buildpackage_default
 }
+
+function update_upstream() {
+	logmust update_upstream_from_git
+}