Remove redundant namespace references

Signed-off-by: methylDragon <[email protected]>

Author: methylDragon

include/ignition/gazebo/EntityComponentManager.hh

@@ -22,6 +22,7 @@
 
 #include <map>
 #include <memory>
+#include <optional>
 #include <set>
 #include <string>
 #include <typeinfo>

include/ignition/gazebo/detail/EntityComponentManager.hh

@@ -19,6 +19,7 @@
 
 #include <cstring>
 #include <map>
+#include <optional>
 #include <set>
 #include <type_traits>
 #include <utility>

src/Component_TEST.cc

@@ -321,7 +321,7 @@ TEST_F(ComponentTest, OStream)
     EXPECT_EQ("Mass: 0", ostr.str());
   }
 
-  // Component with a ignition::msgs type that gets serialized by the default
+  // Component with a msgs type that gets serialized by the default
   // serializer
   {
     using Custom = components::Component<msgs::Int32, class CustomTag,
@@ -473,7 +473,7 @@ TEST_F(ComponentTest, IStream)
     EXPECT_DOUBLE_EQ(200, comp.Data()->MassMatrix().Mass());
   }
 
-  // Component with a ignition::msgs type that gets deserialized by the message
+  // Component with a msgs type that gets deserialized by the message
   // deserializer
   {
     using Custom = components::Component<msgs::Int32, class CustomTag,