Update Resultstore UI base link from source.cloud to btx

Bug: 323387977
Test: local
Change-Id: I2467b2d82161bd3306fd97e8c131c678c9ec57d9
diff --git a/tools/results_uploader/src/resultstore_client.py b/tools/results_uploader/src/resultstore_client.py
index 200a837..662ed1a 100644
--- a/tools/results_uploader/src/resultstore_client.py
+++ b/tools/results_uploader/src/resultstore_client.py
@@ -27,7 +27,7 @@
 import httplib2
 
 _DEFAULT_CONFIGURATION = 'default'
-_RESULTSTORE_BASE_LINK = 'https://source.cloud.google.com/results/invocations'
+_RESULTSTORE_BASE_LINK = 'https://btx.cloud.google.com/invocations'
 
 _STATUS_PASSED = 'PASSED'
 _STATUS_FAILED = 'FAILED'