Move Antlr 2.7.7 version management from gradle/dependency-management.gradle to gradle.properties.

ANTLR is a primary dependency of Apache Geode.

gradle.properties

@@ -1,5 +1,6 @@
 org.gradle.jvmargs=-Xmx2g -Dfile.encoding=UTF-8
 deployDocsHost=docs-ip.spring.io
+antlrVersion=2.7.7
 apacheGeodeVersion=1.14.4
 springVersion=5.3.23
 springBootVersion=2.6.12

gradle/dependency-management.gradle

@@ -1,5 +1,4 @@
 // Define dependency version properties
-ext['antlrVersion'] = '2.7.7'
 ext['apacheTaglibsVersion'] = '1.2.5'
 ext['assertjVersion'] = '3.22.0'
 ext['javaxServletApiVersion'] ='4.0.4'