[Ops] Skip buildkite hooks for non kibana jobs (#165597)

## Summary

Kibana's build jobs work on a different subset of executors than the
buildkite pipelines defined in `catalog-info.yaml`.

The former jobs require a set of `pre_command` / `post_command` steps to
prepare the jobs for building/testing kibana.
The latter don't have access rights to certain vault secrets (and
possibly other missing config from the Kibana world), but for now,
they're also not building Kibana, they just trigger other jobs, so we
can just skip the problematic hooks.

~~A probably good indicator I found for deciding whether we need the
kibana-related `pre_command` is the
`BUILDKITE_AGENT_META_DATA_AGENT_MANAGER` flag, that's set to `"kibana"`
in the case of the kibana executors.~~

We can try to match on the agent names for the CI-systems agents. They
seem to be starting with `bk-agent`.

This should allow for the
[kibana-tests](https://buildkite.com/elastic/kibana-tests) job to run.

Split from: https://github.com/elastic/kibana/pull/165346

---------

Co-authored-by: Tiago Costa <tiago.costa@elastic.co>

.buildkite/hooks/post-command

@@ -1,3 +1,7 @@
 #!/usr/bin/env bash
 
-.buildkite/scripts/lifecycle/post_command.sh
+if [[ "$BUILDKITE_AGENT_NAME" =~ ^bk-agent ]]; then
+  echo "Pipeline file triggered from outside the kibana executors, skipping post_command"
+else
+  .buildkite/scripts/lifecycle/post_command.sh
+fi

.buildkite/hooks/pre-command

@@ -1,3 +1,7 @@
 #!/usr/bin/env bash
 
-source .buildkite/scripts/lifecycle/pre_command.sh
+if [[ "$BUILDKITE_AGENT_NAME" =~ ^bk-agent ]]; then
+  echo "Pipeline file triggered from outside the kibana executors, skipping pre_command"
+else
+  source .buildkite/scripts/lifecycle/pre_command.sh
+fi

.buildkite/pipelines/quality-gates/pipeline.tests-production.yaml

@@ -1,3 +1,7 @@
+env:
+  TEAM_CHANNEL: "#kibana-serverless-release"
+  ENVIRONMENT: "production"
+
 steps:
   - label: ":pipeline::fleet::seedling: Trigger Observability Kibana Tests for ${ENVIRONMENT}"
     command: echo "replace me with Observability specific Kibana tests"
@@ -8,3 +12,10 @@ steps:
     command: echo "replace me with Security specific Kibana tests"
     agent:
       image: "docker.elastic.co/ci-agent-images/basic-buildkite-agent:1688566364"
+
+  - wait: ~
+
+  - label: ":judge::seedling: Trigger Manual Tests Phase"
+    command: "make -C /agent trigger-manual-verification-phase"
+    agents:
+      image: "docker.elastic.co/ci-agent-images/manual-verification-agent:0.0.1"

.buildkite/pipelines/quality-gates/pipeline.tests-qa.yaml

@@ -1,3 +1,7 @@
+env:
+  TEAM_CHANNEL: "#kibana-serverless-release"
+  ENVIRONMENT: "qa"
+
 steps:
   - label: ":pipeline::kibana::seedling: Trigger Kibana Tests for ${ENVIRONMENT}"
     command: echo "replace me with Kibana specific tests"
@@ -18,3 +22,10 @@ steps:
     command: echo "replace me with Control Plane specific Kibana tests"
     agent:
       image: "docker.elastic.co/ci-agent-images/basic-buildkite-agent:1688566364"
+
+  - wait: ~
+
+  - label: ":judge::seedling: Trigger Manual Tests Phase"
+    command: "make -C /agent trigger-manual-verification-phase"
+    agents:
+      image: "docker.elastic.co/ci-agent-images/manual-verification-agent:0.0.1"

.buildkite/pipelines/quality-gates/pipeline.tests-staging.yaml

@@ -1,3 +1,7 @@
+env:
+  TEAM_CHANNEL: "#kibana-serverless-release"
+  ENVIRONMENT: "staging"
+
 steps:
   - label: ":pipeline::fleet::seedling: Trigger Observability Kibana Tests for ${ENVIRONMENT}"
     command: echo "replace me with Observability specific Kibana tests"
@@ -8,3 +12,10 @@ steps:
     command: echo "replace me with Security specific Kibana tests"
     agent:
       image: "docker.elastic.co/ci-agent-images/basic-buildkite-agent:1688566364"
+
+  - wait: ~
+
+  - label: ":judge::seedling: Trigger Manual Tests Phase"
+    command: "make -C /agent trigger-manual-verification-phase"
+    agents:
+      image: "docker.elastic.co/ci-agent-images/manual-verification-agent:0.0.1"

.buildkite/scripts/lifecycle/pre_command.sh

@@ -2,11 +2,6 @@
 
 set -euo pipefail
 
-if [[ "$BUILDKITE_COMMAND" =~ ^"buildkite-agent pipeline upload" ]]; then
-  echo "Skipped pre-command when running the Upload pipeline"
-  exit 0
-fi
-
 source .buildkite/scripts/common/util.sh
 
 echo '--- Setup environment vars'