parse_audit_log not working with td-agent

Question

I have installed the td-agent with version td-agent-4.1.0-1.el7.x86_64 on CentOS7. I'm not able to load the gem.

# td-agent-gem install fluent-plugin-filter-parse-audit-log
Fetching fluent-plugin-filter-parse-audit-log-0.1.2.gem
Fetching audit_log_parser-0.1.3.gem
Successfully installed audit_log_parser-0.1.3
Successfully installed fluent-plugin-filter-parse-audit-log-0.1.2
Parsing documentation for audit_log_parser-0.1.3
Installing ri documentation for audit_log_parser-0.1.3
Parsing documentation for fluent-plugin-filter-parse-audit-log-0.1.2
Installing ri documentation for fluent-plugin-filter-parse-audit-log-0.1.2
Done installing documentation for audit_log_parser, fluent-plugin-filter-parse-audit-log after 0 seconds
2 gems installed

Input config:

<source>
  @type tail
  path /var/log/audit/audit.log
  pos_file /var/log/td-agent/audit.pos
  tag syslog.audit
  <parse>
    @type parse_audit_log
  </parse>
</source>

Error to load parse_audit_log

   # /opt/td-agent/bin/fluentd --dry-run --config /etc/td-agent/td-agent.conf
    2021-03-24 15:01:19 +0000 [info]: parsing config file is succeeded path="/etc/td-agent/td-agent.conf"
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-elasticsearch' version '4.3.3'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-filter-parse-audit-log' version '0.1.2'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-flowcounter-simple' version '0.1.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-kafka' version '0.16.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-prometheus' version '1.8.5'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-prometheus_pushgateway' version '0.0.2'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-record-modifier' version '2.1.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-rewrite-tag-filter' version '2.3.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-s3' version '1.5.1'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-sd-dns' version '0.1.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-systemd' version '1.0.2'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-td' version '1.1.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluent-plugin-webhdfs' version '1.4.0'
    2021-03-24 15:01:19 +0000 [info]: gem 'fluentd' version '1.12.1'
    2021-03-24 15:01:19 +0000 [info]: starting fluentd-1.12.1 as dry run mode ruby="2.7.2"
    2021-03-24 15:01:19 +0000 [warn]: [output_td] Use different plugin for secondary. Check the plugin works with primary like secondary_file primary="Fluent::Plugin::TreasureDataLogOutput" secondary="Fluent::Plugin::FileOutput"
    2021-03-24 15:01:20 +0000 [error]: config error file="/etc/td-agent/td-agent.conf" error_class=Fluent::ConfigError error="Unknown parser plugin 'parse_audit_log'. Run 'gem search -rd fluent-plugin' to find plugins"

Could you please let me know what are the way to load plugins? I have followed the https://docs.fluentd.org/deployment/plugin-management#for-td-agent but still some issues while restarting the service with systemctl.