fix(set-kernel-config): trim config lines with sed instead of xargs

xargs interprets single quotes in comment lines (e.g. "can't" in the
FUSE-BPF header) and dies with 'unmatched single quote' before the
comment guard can skip them. Replace with a pure whitespace trim via
sed, which does no quote parsing.

.github/actions/set-kernel-config/action.yml

@@ -25,7 +25,7 @@ runs:
 
       apply_line() {
         local line="$1"
-        line="$(echo "$line" | xargs)"
+        line="$(echo "$line" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')"
 
         # skip empty/comments
         [[ -z "$line" || "$line" == \#* ]] && return