Catch URL error if remote stats bucket does not exist

When creating a new IP or moving an IP to ipgen, there is no initial
regression run. Consequently, fetching its stats fails as the remote
path does not exist.

To unblock this error, this PR catches the URL error if the path does
not exist and returns that 0 runs out of 0 are performed.

Signed-off-by: Robert Schilling <rschilling@rivosinc.com>

util/site/fetch_block_stats.py

@@ -8,6 +8,7 @@
 and bundles it into one json file.
 """
 from urllib.request import urlopen
+from urllib.error import HTTPError
 import itertools as it
 import json
 from pathlib import Path
@@ -57,8 +58,12 @@
 
 
 def parse_report(path: str) -> Tuple[int, int]:
-    with urlopen(f'https://reports.opentitan.org/{path}/report.json') as response:
-        report = json.load(response)
+    try:
+        with urlopen(f'https://reports.opentitan.org/{path}/report.json') as response:
+            report = json.load(response)
+    except HTTPError:
+        # URL does not exist, there are no test runs yet for that
+        return (0, 0)
 
     # Extract all tests from the report.
     testpoints = report['results']['testpoints']