obs/_generic: small improvements

 * use cp instead of mv so that the original file doesn't disappear and we
can rerun the script
 * osc rm can fail if the package is empty (especially at creation time
of the package)

obs/_generic/build-scripts/20obs.sh

@@ -9,7 +9,7 @@ source _generic/build-scripts/00env.sh
 osc checkout "$OBS_PROJECT" "$OBS_PACKAGE" || true
 cd "$OBS_DIR"
 osc update
-osc rm -f "$SOFTWARE_AND_VERSION$ARCHIVE_EXT" "$SOFTWARE_AND_VERSION".dsc
+osc rm "$SOFTWARE_AND_VERSION$ARCHIVE_EXT" "$SOFTWARE_AND_VERSION".dsc || true
 cd "$INITIAL_DIR"
 
 # copy compilation files and override the files from _generic
@@ -22,7 +22,7 @@ copy_and_solve_templates "$DISTRIB_FILES_SOFTWARE_DIR" "$OBS_DIR"
 
 ### Finalize the tarball directory preparation
 # switch to the buildout wrapper for OBS
-mv "$TARBALL_DIR/obs_buildout.cfg" "$RUN_BUILDOUT_DIR/buildout.cfg"
+cp "$TARBALL_DIR/obs_buildout.cfg" "$RUN_BUILDOUT_DIR/buildout.cfg"
 # save the local $TARBALL_DIR path so that it is replaced by the $TARBALL_DIR path from OBS' VM
 echo "$TARBALL_DIR" > "$TARBALL_DIR"/local_tarball_directory_path
 # add a stamp so that OBS does not clean the local preparation before compiling