Remove unused tracking

We are not using the data collected (data minimisation) from this tracking and we users are not aware of it happening since there is no cookie banner (consent).

- [GDPR Data
Minimisation](https://ico.org.uk/for-organisations/guide-to-data-protection/guide-to-the-general-data-protection-regulation-gdpr/principles/data-minimisation/)
- [GDPR Consent](https://ico.org.uk/for-organisations/guide-to-data-protection/guide-to-the-general-data-protection-regulation-gdpr/lawful-basis-for-processing/consent/)

config/tech-docs.yml

@@ -18,7 +18,7 @@ service_link: /
 max_toc_heading_level: 2
 
 # Tracking ID from Google Analytics (e.g. UA-XXXX-Y)
-ga_tracking_id: UA-86101042-3
+# ga_tracking_id: UA-XXXX-Y
 
 google_site_verification: "IJ5HOXpZrISM6la-YO_iX0rBUC5YFftpexygcKLsNs4"