chore(NA): reduce parallelism number on Serverless Security Cypress Tests (#165906)

This PR reduces the parallel number of workers that will run the
Serverless Security Cypress Tests for now. As we have skipped some
serverless tests that were flaky we don't need as much workers as
before. As soon as we see those pipeline times increasing we can restore
the number of workers.

.buildkite/pipelines/pull_request/base.yml

@@ -140,7 +140,7 @@ steps:
       queue: n2-4-spot
     depends_on: build
     timeout_in_minutes: 40
-    parallelism: 12
+    parallelism: 2
     soft_fail: true
     retry:
       automatic:
@@ -166,7 +166,7 @@ steps:
       queue: n2-4-spot
     depends_on: build
     timeout_in_minutes: 40
-    parallelism: 6
+    parallelism: 2
     soft_fail: true
     retry:
       automatic:

.buildkite/pipelines/serverless.yml

@@ -105,32 +105,33 @@ steps:
       queue: n2-4-spot
     depends_on: build
     timeout_in_minutes: 40
-    parallelism: 12
-    retry:
-      automatic:
-        - exit_status: '*'
-          limit: 1
-
-  - command: .buildkite/scripts/steps/functional/security_serverless_explore.sh
-    label: 'Serverless Explore - Security Solution Cypress Tests'
-    agents:
-      queue: n2-4-spot
-    depends_on: build
-    timeout_in_minutes: 60
-    parallelism: 4
+    parallelism: 2
     retry:
       automatic:
         - exit_status: '*'
           limit: 1
 
   - command: .buildkite/scripts/steps/functional/security_serverless_investigations.sh
-    label: 'Serverless Investigations - Security Solution Cypress Tests'
+    label: 'Serverless Security Investigations Cypress Tests'
     agents:
       queue: n2-4-spot
     depends_on: build
     timeout_in_minutes: 120
-    parallelism: 6
+    parallelism: 2
     retry:
       automatic:
         - exit_status: '*'
           limit: 1
+
+  - command: .buildkite/scripts/steps/functional/security_serverless_explore.sh
+    label: 'Serverless Security Explore Cypress Tests'
+    agents:
+      queue: n2-4-spot
+    depends_on: build
+    timeout_in_minutes: 60
+    parallelism: 2
+    retry:
+      automatic:
+        - exit_status: '*'
+          limit: 1
+