Prepare for 9.0.0-rc1

Author: mark-vieira

.buildkite/scripts/dra-update-staging.sh

@@ -37,7 +37,7 @@ for BRANCH in "${BRANCHES[@]}"; do
 
   if [[ "$SHOULD_TRIGGER" == "true" ]]; then
     if [[ "$BRANCH" == "9.0" ]]; then
-      export VERSION_QUALIFIER="beta1"
+      export VERSION_QUALIFIER="rc1"
     fi
     echo "Triggering DRA staging workflow for $BRANCH"
     cat << EOF | buildkite-agent pipeline upload

.buildkite/scripts/dra-workflow.trigger.sh

@@ -8,7 +8,7 @@ source .buildkite/scripts/branches.sh
 
 for BRANCH in "${BRANCHES[@]}"; do
   if [[ "$BRANCH" == "9.0" ]]; then
-    export VERSION_QUALIFIER="beta1"
+    export VERSION_QUALIFIER="rc1"
   fi
 
   INTAKE_PIPELINE_SLUG="elasticsearch-intake"