[k6] Add JVM warmup phase (#2)

To account for JVM warmup effect, the k6 test suite is run twice:
initially, the whole test suite is run without recording results.

- Added environment variables to allow setting total CM-handles and
  batch size for registration. By reducing total CM-handles during
  warm-up, many more operations will be run.

Issue-ID: CPS-2264
Signed-off-by: danielhanrahan <daniel.hanrahan@est.tech>
Change-Id: Ib1d1e76d31719d788a3e026797faa0a425b320a2
diff --git a/k6-tests/ncmp/common/utils.js b/k6-tests/ncmp/common/utils.js
index 1fb9b8e..55ef60a 100644
--- a/k6-tests/ncmp/common/utils.js
+++ b/k6-tests/ncmp/common/utils.js
@@ -20,7 +20,8 @@
 
 export const NCMP_BASE_URL = 'http://localhost:8883';
 export const DMI_PLUGIN_URL = 'http://ncmp-dmi-plugin-demo-and-csit-stub:8092';
-export const TOTAL_CM_HANDLES = 20000
+export const TOTAL_CM_HANDLES = Number(__ENV.TOTAL_CM_HANDLES) || 20000;
+export const REGISTRATION_BATCH_SIZE = Number(__ENV.REGISTRATION_BATCH_SIZE) || 100;
 
 /**
  * Generates a batch of CM-handle IDs based on batch size and number.