Add retries to PR pipeline steps (#15787) (#15794)

There is occasional flakiness mainly with IT tests requiring us to
manually retry such failures when we raise PR (or the first
group of the exhaustive suite, which runs the same steps).

This commit adds up to 3 retries for all the steps of the PR
pipeline.

(cherry picked from commit 739e8a3ef0)

Co-authored-by: Dimitrios Liappis <dimitrios.liappis@gmail.com>

.buildkite/pull_request_pipeline.yml

@@ -8,6 +8,9 @@ steps:
       cpu: "4"
       memory: "6Gi"
       ephemeralStorage: "100Gi"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -23,6 +26,9 @@ steps:
       cpu: "4"
       memory: "8Gi"
       ephemeralStorage: "100Gi"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -36,6 +42,9 @@ steps:
       cpu: "8"
       memory: "16Gi"
       ephemeralStorage: "100Gi"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
       if [[ $BUILDKITE_PULL_REQUEST == "false" ]]; then
@@ -59,6 +68,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as a non-root user
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -74,6 +86,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as a non-root user
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -89,6 +104,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as non root (logstash) user. UID is hardcoded in image.
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -105,6 +123,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as non root (logstash) user. UID is hardcoded in image.
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -121,6 +142,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as non root (logstash) user. UID is hardcoded in image.
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail
 
@@ -136,6 +160,9 @@ steps:
       ephemeralStorage: "100Gi"
       # Run as non root (logstash) user. UID is hardcoded in image.
       imageUID: "1002"
+    retry:
+      automatic:
+        - limit: 3
     command: |
       set -euo pipefail