[IMP] fields: use ignored field for respawn

When a field reappears after an upgrade, a log with the format
"field ... has respawn!" is emited. In some case, it is possible that
this error should be silenced.

The current case was because an upgrade script targeting 18.2 was merged
during the freeze and should target 18.3. During a short time frame
after a freeze, some branch may be tested without testing the upgrade
from the freshly created branch since no template are available.

In this case, a script was merged with an invalid version number. A pull
request (#7240) was created to fix it but it took some time to be merged
and then to be used by latest builds.

An exeption was added in master, fixing the 18.2-> master but this
exception was not working for the 18.*->18.2 error. This commit will
use the same exception to silence this error allowing quick fixes in
this kind of situation.

closes #213

Related: odoo/upgrade#7261
Signed-off-by: Christophe Simonis (chs) <chs@odoo.com>
Co-authored-by: Christophe Simonis <chs@odoo.com>

Author: Xavier-Do

src/base/0.0.0/end-no-respawn-fields.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 import logging
+import os
 
 from psycopg2.extras import execute_values
 
@@ -40,10 +41,22 @@ def migrate(cr, version):
     """
     )
 
+    key = "field_respawn:"
+    ignored_fields_respawn = {
+        e[len(key) :]
+        for e in os.environ.get("suppress_upgrade_warnings", "").split(",")  # noqa: SIM112
+        if e.startswith(key)
+    }
+
     for model, field, transient, store in cr.fetchall():
         qualifier = "field" if store else "non-stored field"
         if transient:
             qualifier = "transient " + qualifier
         lvl = util.NEARLYWARN if transient or not store else logging.CRITICAL
+        action = ""
+
+        if "{}/{}".format(model, field) in ignored_fields_respawn:
+            lvl = util.NEARLYWARN
+            action = "; explicitly ignored"
 
-        _logger.log(lvl, "%s %s/%s has respawn!", qualifier, model, field)
+        _logger.log(lvl, "%s %s/%s has respawn%s.", qualifier, model, field, action)