[EDR Workflows][CI][8.11] Indicate in the name of burning specs that they're only soft failing (#172671)

## Summary

Backport of #172589

Goal: emphasise in our job names that they're soft failing.

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

.buildkite/pipelines/pull_request/defend_workflows.yml

@@ -12,7 +12,7 @@ steps:
           limit: 1
 
   - command: .buildkite/scripts/steps/functional/defend_workflows_burn.sh
-    label: 'Defend Workflows Cypress Tests, burning changed specs'
+    label: '[Soft fail] Defend Workflows Cypress Tests, burning changed specs'
     agents:
       queue: n2-4-virt
     depends_on: build

.buildkite/pipelines/pull_request/osquery_cypress.yml

@@ -14,7 +14,7 @@ steps:
       - "target/kibana-osquery/**/*"
 
   - command: .buildkite/scripts/steps/functional/osquery_cypress_burn.sh
-    label: 'Osquery Cypress Tests, burning changed specs'
+    label: '[Soft fail] Osquery Cypress Tests, burning changed specs'
     agents:
       queue: n2-4-spot
     depends_on: build

.buildkite/pipelines/pull_request/security_solution.yml

@@ -36,7 +36,7 @@ steps:
           limit: 1
 
   - command: .buildkite/scripts/steps/functional/security_solution_burn.sh
-    label: 'Security Solution Cypress tests, burning changed specs'
+    label: '[Soft fail] Security Solution Cypress tests, burning changed specs'
     agents:
       queue: n2-4-spot
     depends_on: build