Typo fix

Author: DelazJ

docs/user_manual/appendices/qgis_file_formats.rst

@@ -16,7 +16,7 @@ QGS/QGZ - The QGIS Project File Format
 The **QGS** format is an XML format for storing QGIS projects.
 The **QGZ** format is a compressed (zip) archive containing a
 QGS file and a QGD file.
-The **QGD** file is the associated sqlite database of the qgis
+The **QGD** file is the associated SQLite database of the qgis
 project that contain auxiliary data for the project.
 If there are no auxiliary data, the QGD file will be empty.