update theHarvester version lookup command

web/fixtures/external_tools.yaml

@@ -198,10 +198,10 @@
       names, subdomains, IPs and URLs using multiple public data sources.
     github_url: https://github.com/laramies/theHarvester
     license_url: https://github.com/laramies/theHarvester/blob/master/README/LICENSES
-    version_lookup_command: grep -oP '(?<=theHarvester )\d+\.\d+\.\d+' <<< "$(python3 theHarvester.py -h)"
+    version_lookup_command: cat /usr/src/github/theHarvester/theHarvester/lib/version.py
     update_command: git pull
     install_command: git clone https://github.com/laramies/theHarvester
-    version_match_regex: (\d+\.\d+\.\d+)
+    version_match_regex: \b\d+\.\d+\.\d+\b
     is_default: true
     is_subdomain_gathering: false
     is_github_cloned: true
@@ -328,4 +328,4 @@
     is_subdomain_gathering: false
     is_github_cloned: false
     github_clone_path: null
-    subdomain_gathering_command: null
+    subdomain_gathering_command: null