Correct a missing instance of s/80/50/

Signed-off-by: Jonathan Dowland <[email protected]>

Author: jmtd

modules/jvm/api/module.yaml

@@ -14,7 +14,7 @@ envs:
   description: User specified Java options to be appended to generated options in JAVA_OPTS.
   example: "-Dsome.property=foo"
 - name: JAVA_MAX_MEM_RATIO
-  description:  Specify the maximum heap memory. Corresponds to the JVM argument `-XX:MaxRAMPercentage`. The default is `50.0` which means 80% of the available memory. You can disable this mechanism by setting the value to `0`.
+  description:  Specify the maximum heap memory. Corresponds to the JVM argument `-XX:MaxRAMPercentage`. The default is `50.0` which means 50% of the available memory. You can disable this mechanism by setting the value to `0`.
   example: "90.0"
 - name: JAVA_INITIAL_MEM_RATIO
   description: