Fix source tarball creation: write archive outside source tree to avoid tar exit 1

increment_and_push.sh

@@ -199,13 +199,19 @@ build_release_binary() {
 create_source_tarball() {
     local tarball_name="signer-${NEW_VERSION#v}.tar.gz"
 
-    if tar -czf "$tarball_name" \
+    # Write the archive OUTSIDE the tree being archived. Writing it into the
+    # current directory makes tar exit 1 with "file changed as we read it",
+    # which previously caused the tarball to be silently skipped.
+    local tarball_path
+    tarball_path="$(mktemp -d)/${tarball_name}"
+
+    if tar -czf "$tarball_path" \
         --exclude='target/*' \
         --exclude='.git*' \
         --exclude='*.log' \
         --exclude='*.tar.gz' \
         . > /dev/null 2>&1; then
-        echo "$tarball_name"
+        echo "$tarball_path"
     else
         return 1
     fi