Disable mbedtls-gather-timestamps

Since PR merge and PR head jobs are not available yet

Signed-off-by: Arthur She <arthur.she@linaro.org>
Change-Id: I624894ba3ad7ad5807a2311164d44f84f72c5273
diff --git a/mbedtls-gather-timestamps.yaml b/mbedtls-gather-timestamps.yaml
index 86e9339..ffc31c5 100644
--- a/mbedtls-gather-timestamps.yaml
+++ b/mbedtls-gather-timestamps.yaml
@@ -2,6 +2,7 @@
     concurrent: true
     description: Mbed TLS job to gather timestamps from various jobs' runs
     name: mbedtls-gather-timestamps
+    disabled: true
     pipeline-scm:
       lightweight-checkout: true
       scm: