Remove team from alerts yml for global_search

High level details of Slack discussion

• #g_global_search is receiving duplicate alerts when gitlab_search_indexing_queue_backing_up is fired (and resolved)
• reviewed alerts defined via https://prometheus-gke.gprd.gitlab.net/rules
• during review noticed that other alerts for global_search do not have team defined, only feature_category: https://alerts.gitlab.net/#/status
• decision is to remove team from definition

Click to expand receiver info

  - receiver: team_global_search_alerts_channel
    matchers:
    - env="gprd"
    - feature_category="global_search"
    continue: true

...

  - receiver: team_global_search_alerts_channel
    matchers:
    - env="gprd"
    - team="global_search"
    continue: true