Migrate to PowSyBl 4.7.0 (#24)

Signed-off-by: Geoffroy Jamgotchian <[email protected]>

Author: geofjamg

pom.xml

@@ -35,7 +35,7 @@
 
     <properties>
         <java.version>11</java.version>
-        <gridsuite-dependencies.version>14</gridsuite-dependencies.version>
+        <gridsuite-dependencies.version>15</gridsuite-dependencies.version>
         <string-template.version>4.3.1</string-template.version>
         <commons-lang3.version>3.9</commons-lang3.version>
         <liquibase-hibernate-package>org.gridsuite.mapping.server</liquibase-hibernate-package>