STEP: Rename generic Import/Export dialog title

Closes FreeCAD#16415

Author: luzpaz

src/Mod/Part/Gui/DlgExportStep.ui

@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string notr="true">STEP</string>
+   <string notr="true">STEP Export Settings</string>
   </property>
   <layout class="QGridLayout" name="gridLayout_4">
    <property name="margin">

src/Mod/Part/Gui/DlgImportStep.ui

@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string notr="true">STEP</string>
+   <string notr="true">STEP Import Settings</string>
   </property>
   <layout class="QGridLayout" name="gridLayout_4">
    <item row="1" column="0">