[7.9] [baseline/capture] use high-memory nodes with ramDisks (#71894) (#72210)

Co-authored-by: spalger <spalger@users.noreply.github.com>

Author: Spencer

.ci/Jenkinsfile_baseline_capture

@@ -8,12 +8,12 @@ kibanaPipeline(timeoutMinutes: 120) {
     catchError {
       parallel([
         'oss-visualRegression': {
-          workers.ci(name: 'oss-visualRegression', size: 's', ramDisk: false) {
+          workers.ci(name: 'oss-visualRegression', size: 's-highmem', ramDisk: true) {
             kibanaPipeline.functionalTestProcess('oss-visualRegression', './test/scripts/jenkins_visual_regression.sh')(1)
           }
         },
         'xpack-visualRegression': {
-          workers.ci(name: 'xpack-visualRegression', size: 's', ramDisk: false) {
+          workers.ci(name: 'xpack-visualRegression', size: 's-highmem', ramDisk: true) {
             kibanaPipeline.functionalTestProcess('xpack-visualRegression', './test/scripts/jenkins_xpack_visual_regression.sh')(1)
           }
         },