Remove duplicate declarative config resolver (#8579)

Signed-off-by: Develop-KIM <kimdonghwan913@gmail.com>

Author: Develop-KIM

api/incubator/src/main/java/io/opentelemetry/api/incubator/config/DeclarativeConfigPropertyUtil.java

@@ -31,7 +31,6 @@ private DeclarativeConfigPropertyUtil() {}
               DeclarativeConfigPropertyUtil::getBooleanList,
               DeclarativeConfigPropertyUtil::getLongList,
               DeclarativeConfigPropertyUtil::getDoubleList,
-              DeclarativeConfigPropertyUtil::getStringList,
               DeclarativeConfigPropertyUtil::getStructuredList,
               DeclarativeConfigPropertyUtil::getStructured);