Bump spark-core from 2.5.5 to 2.7.2

Bumps [spark-core](https://github.com/perwendel/spark) from 2.5.5 to 2.7.2.
- [Release notes](https://github.com/perwendel/spark/releases)
- [Commits](perwendel/spark@2.5.5...2.7.2)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

pom.xml

@@ -11,7 +11,7 @@
     <inceptionYear>2021</inceptionYear>
 
     <properties>
-        <spark.version>2.5.5</spark.version>
+        <spark.version>2.7.2</spark.version>
         <slf4j.version>1.7.13</slf4j.version>
         <jetty.version>9.3.6.v20151106</jetty.version>
         <junit.version>5.7.0</junit.version>