Upgrade to Byte Buddy 1.6.12

Closes gh-8852

spring-boot-dependencies/pom.xml

@@ -54,7 +54,7 @@
 		<assertj.version>3.6.2</assertj.version>
 		<atomikos.version>3.9.3</atomikos.version>
 		<bitronix.version>2.1.4</bitronix.version>
-		<byte-buddy.version>1.6.0</byte-buddy.version>
+		<byte-buddy.version>1.6.12</byte-buddy.version>
 		<caffeine.version>2.4.0</caffeine.version>
 		<cassandra-driver.version>3.1.4</cassandra-driver.version>
 		<classmate.version>1.3.3</classmate.version>