Regex doesn't work - metricbeat system module

[jasony (Jason)]

metricbeat.modules:
- module: system
  metricsets: ["process"]
  enabled: true
  period: 60s
  processes: ['^.*logstash.*$']
  fields:
    dc: doj-dev
    host: "doj-dev-elk-col-01"
    cluster_type: "collector"
...

$ ps -ef | grep logstash
onmadm   30293     1  0 Apr30 ?        03:12:49 /bin/java -Xms1g -Xmx1g -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -Djava.awt.headless=true -Dfile.encoding=UTF-8 -Djruby.compile.invokedynamic=true -Djruby.jit.threshold=0 -XX:+HeapDumpOnOutOfMemoryError -Djava.security.egd=file:/dev/urandom -cp /app/logstash/logstash-core/lib/jars/animal-sniffer-annotations-1.14.jar:/app/logstash/logstash-core/lib/jars/commons-codec-1.11.jar:/app/logstash/logstash-core/lib/jars/commons-compiler-3.0.8.jar:/app/logstash/logstash-core/lib/jars/error_prone_annotations-2.0.18.jar:/app/logstash/logstas -core/lib/jars/google-java-format-1.1.jar:/app/logstash/logstash-core/lib/jars/gradle-license-report-0.7.1.jar:/app/logstash/logstash-core/lib/jars/guava-22.0.jar:/app/logstash/logstash-core/lib/jars/j2objc-annotations-1.1.jar:/app/logstash/logstash-core/lib/jars/jackson-annotations-2.9.8.jar:/app/logstash/logstash-core/lib/jars/jackson-core-2.9.8.jar:/app/logstash/logstash-core/lib/jars/jackson-databind-2.9.8.jar:/app/logstash/logstash-core/lib/jars/jackson-dataformat-cbor-2.9.8.jar:/app/logstash/logstash-core/lib/jars/janino-3.0.8.jar:/app/logstash/logstash-core/lib/jars/javassist-3.22.0-GA.jar:/app/logstash/logstash-core/lib/jars/jruby-complete-9.2.6.0.jar:/app/logstash/logstash-core/lib/jars/jsr305-1.3.9.jar:/app/logstash/logstash-core/lib/jars/log4j-api-2.9.1.jar:/app/logstash/logstash-core/lib/jars/log4j-core-2.9.1.jar:/app/logstash/logstash-core/lib/jars/log4j-slf4j-impl-2.9.1.jar:/app/logstash/logstash-core/lib/jars/logstash-core.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.commands-3.6.0.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.contenttype-3.4.100.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.expressions-3.4.300.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.filesystem-1.3.100.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.jobs-3.5.100.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.resources-3.7.100.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.core.runtime-3.7.0.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.equinox.app-1.3.100.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.equinox.common-3.6.0.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.equinox.preferences-3.4.1.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.equinox.registry-3.5.101.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.jdt.core-3.10.0.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.osgi-3.7.1.jar:/app/logstash/logstash-core/lib/jars/org.eclipse.text-3.5.101.jar:/app/logstash/logstash-core/lib/jars/slf4j-api-1.7.25.jar org.logstash.Logstash -f /app/logstash/jmx_mon.conf --path.data /appdata/logstash-jmx-mon --path.logs /applog/logstash-jmx-mon

hello,
i am trying to collect a specific process information and use regex in "processes" field with Metricbeat module "system", but my .yml is NOT getting any processes information.

does my regex wrong? processes: ['^.logstash.$'] if so, please advice.

thank you!