add soft BioEstimation unit_test

add soft BioEstimation unit_test

test/test_soft_biometrics_estimation.test

+<launch> 
+    <arg name="input_topic" default="/head_front_camera/color/image_raw/compressed/"/>
+
+    <node pkg="wp4_soft_biometrics_estimation" type="soft_biometrics_estimation.py" respawn="true" name="soft_biometrics_estimation">
+        <param name="input_topic" type="string" value="$(arg input_topic)"/>
+    </node>
+    <test test-name="test_soft_biometrics_estimation" pkg="wp4_soft_biometrics_estimation" type="unittest_soft_biometrics_estimation.py" />
+</launch>