Deprecate 24 Webcast pages - Batch2

## Goal
We would like to deprecate the following solutions pages because they have no meaningful traffic from any source and no backlinks.

|  Webcast Pages to Deprecate                                                    |
|------------------------------------------------------------------------------------------------|
| https://about.gitlab.com/webcast/integration-developpement-deploiement-continus-cloud/         |                   
| https://about.gitlab.com/webcast/justcommit-reduce-cycle-time/                                 |
| https://about.gitlab.com/webcast/keys-to-devops-success-portugese/                             |
| https://about.gitlab.com/webcast/keys-to-devops-success-spanish/                               |
| https://about.gitlab.com/webcast/keys-to-devops-success/                                       |
| https://about.gitlab.com/webcast/managing-compliance-with-gitlab/                              |
| https://about.gitlab.com/webcast/mastering-ci-cd-italian/                                      |
| https://about.gitlab.com/webcast/mastering-continuous-development-fr/                          |
| https://about.gitlab.com/webcast/mastering-continuous-development-portuguese/                  |
| https://about.gitlab.com/webcast/mission-mobility/                                             |
| https://about.gitlab.com/webcast/monthly-release/gitlab-11.0---auto-devops/                    |
| https://about.gitlab.com/webcast/monthly-release/gitlab-11.1---security/                       |
| https://about.gitlab.com/webcast/monthly-release/gitlab-11.2---get-started-and-iterate-faster/ |
| https://about.gitlab.com/webcast/portable-serverless/                                          |
| https://about.gitlab.com/webcast/rethinking-devops-resiliency/                                 |
| https://about.gitlab.com/webcast/sales/bankofirelandwebcast/                                   |
| https://about.gitlab.com/webcast/sales/juniperwebcast/                                         |
| https://about.gitlab.com/webcast/scaled-continuous-integration-and-delivery/                   |
| https://about.gitlab.com/webcast/securing-serverless/                                          |
| https://about.gitlab.com/webcast/starting-scaling-devops/                                      |
| https://about.gitlab.com/webcast/trek10-aws-cicd/                                              |
| https://about.gitlab.com/webcast/weeds-cloud-native/                                           |
| https://about.gitlab.com/webcast/whats-next-for-gitlab/                                        |
| https://about.gitlab.com/webcast/zerotrust-cloudnative/                                        |

These pages were defined in the [IA Refresh Content Audit](https://gitlab.com/gitlab-com/marketing/digital-experience/buyer-experience/-/issues/354). You can find them in the [Cleaned audit - Phase 1 - website refresh spreadsheet](https://docs.google.com/spreadsheets/d/1fCyFV8gHQrE2EWDZNr801RMJiPTIIG-Wcrvd_sPadSM/edit#gid=116929303) in the "Delete" sheet. 

### Jobs To Be Done
* **Situation**: *Pages listed above to removed from the marketing site and if a user hits that URL, they are presented with a 404 page*
* **Motivation**: *We want to reduce the number of pages in the marketing site*
* **Outcome**: *So we can be efficient*

## DCI
[DRI, Consulted, Informed](https://about.gitlab.com/handbook/people-group/directly-responsible-individuals/#dri-consulted-informed-dci)

- [ ] DRI: `TBD`
- [ ] Consulted: @laurenbarker @hsmith-watson 
- [ ] Informed: `Everyone`

## In scope
What is within scope of this request?

- [ ] Remove the listed pages. They most likely exist in the www-gitlab-com repository.
- [ ] Mark the pages as "complete" in the [Cleaned audit - Phase 1 - website refresh spreadsheet] once removed

## Requirements
What are the requirements for this request? Checklist below is an example of common requirements, please check all that apply and adjust as necessary:

- [ ] Copy writing
- [ ] Illustration
- [ ] Custom Graphics
- [ ] Research
- [ ] Data / Analytics
- [ ] UX Design
- [x] Engineering

Story points: 2.0