Fix symbol checking test when compiled with debug symbols (#1474)

* Fix symbol checking test

The test that checks for prefixed binary symbols was broken when
compiled with DebWithRelInfo since it was checking debugging symbols
that broke the heuristics used.

The commit fixes it doing a couple of actions:
 - Include the length of the namespace sdf: 3sdf
 - Check only dynamic symbols being exported

Signed-off-by: Jose Luis Rivero <jrivero@osrfoundation.org>

* Update test/integration/all_symbols_have_version.bash.in

Co-authored-by: Steve Peters <scpeters@openrobotics.org>
Signed-off-by: Jose Luis Rivero <jrivero@osrfoundation.org>

---------

Signed-off-by: Jose Luis Rivero <jrivero@osrfoundation.org>
Co-authored-by: Steve Peters <scpeters@openrobotics.org>
(cherry picked from commit 904706c)

test/integration/all_symbols_have_version.bash.in

@@ -4,7 +4,13 @@ LIBPATH=$1
 VERSIONED_NS=v@PROJECT_VERSION_MAJOR@
 
 # Sanity check - there should be at least one symbol
-NUM_SYMBOLS=$(nm $LIBPATH | grep -e "sdf" | wc -l)
+
+# nm options:
+# -D to get only dynamic symbols exported
+# 3 before the sdf is <length, id> used by
+# mangled symbols in C++ to check for the
+# sdf namespace
+NUM_SYMBOLS=$(nm -D $LIBPATH | grep -e "3sdf" | wc -l)
 
 if [ $NUM_SYMBOLS -eq 0 ]
 then
@@ -13,7 +19,7 @@ then
 fi
 
 # There must be no unversioned symbols
-UNVERSIONED_SYMBOLS=$(nm $LIBPATH | grep -e "sdf" | grep -e "$VERSIONED_NS" -v)
+UNVERSIONED_SYMBOLS=$(nm -D $LIBPATH | grep -e "3sdf" | grep -e "$VERSIONED_NS" -v)
 UNVERSIONED_SYMBOL_CHARS=$(printf "$UNVERSIONED_SYMBOLS" | wc -m)
 
 if [ $UNVERSIONED_SYMBOL_CHARS -ne 0 ]