[CI] Trigger FIPS PR tests when test-fips label is present (elastic#126332) (elastic#126335)

(cherry picked from commit 5706e07)

Author: brianseeders

.buildkite/pipelines/pull-request/part-1-fips.yml

@@ -1,5 +1,7 @@
 config:
-  allow-labels: "Team:Security"
+  allow-labels:
+    - Team:Security
+    - test-fips
 steps:
   - label: part-1-fips
     command: .ci/scripts/run-gradle.sh -Dignore.tests.seed -Dtests.fips.enabled=true checkPart1

.buildkite/pipelines/pull-request/part-2-fips.yml

@@ -1,5 +1,7 @@
 config:
-  allow-labels: "Team:Security"
+  allow-labels:
+    - Team:Security
+    - test-fips
 steps:
   - label: part-2-fips
     command: .ci/scripts/run-gradle.sh -Dignore.tests.seed -Dtests.fips.enabled=true checkPart2

.buildkite/pipelines/pull-request/part-3-fips.yml

@@ -1,5 +1,7 @@
 config:
-  allow-labels: "Team:Security"
+  allow-labels:
+    - Team:Security
+    - test-fips
 steps:
   - label: part-3-fips
     command: .ci/scripts/run-gradle.sh -Dignore.tests.seed -Dtests.fips.enabled=true checkPart3

.buildkite/pipelines/pull-request/part-4-fips.yml

@@ -1,5 +1,7 @@
 config:
-  allow-labels: "Team:Security"
+  allow-labels:
+    - Team:Security
+    - test-fips
 steps:
   - label: part-4-fips
     command: .ci/scripts/run-gradle.sh -Dignore.tests.seed -Dtests.fips.enabled=true checkPart4

.buildkite/pipelines/pull-request/part-5-fips.yml

@@ -1,5 +1,7 @@
 config:
-  allow-labels: "Team:Security"
+  allow-labels:
+    - Team:Security
+    - test-fips
 steps:
   - label: part-5-fips
     command: .ci/scripts/run-gradle.sh -Dignore.tests.seed -Dtests.fips.enabled=true checkPart5