Update placeholder text for missing citation fields

* Presence of the characters "<>" characters do not get rendered in generated email.

solenoid/records/models.py

@@ -72,7 +72,7 @@ def create_citation(paper_data):
         The minimal citation is generated using the author's first name and last name
         and the publication's title and journal (to which it was published).
         If any of the citation fields are missing, the following placeholder text
-        will be used in the citation: "<[CITATION FIELD NAME] UNIDENTIFIED>".
+        will be used in the citation: "<CITATION FIELD NAME> UNIDENTIFIED".
 
         Note: The citation field name will be formatted such that hyphens are removed
               and all characters are uppercase.
@@ -83,7 +83,7 @@ def create_citation(paper_data):
             Volume(Issue), pp.-pp. doi:XX.XXXXX.
         We don't appear to get page number information, so we'll skip that.
         """
-        citation_field_placeholder = "<{field} UNIDENTIFIED>"
+        citation_field_placeholder = "{field} UNIDENTIFIED"
 
         first_init = None
         if first_name := paper_data[Fields.FIRST_NAME]:

solenoid/records/tests/test_models.py

@@ -436,7 +436,7 @@ def test_create_citation_case_9(self):
         self.assertEqual(
             citation,
             "Wilczek, F. (1973). Ultraviolet behavior of "
-            "non-abelian gauge theories. <JOURNAL-NAME UNIDENTIFIED>, "
+            "non-abelian gauge theories. JOURNAL-NAME UNIDENTIFIED, "
             '30(26). <a href="https://doi.org/10.1103/PhysRevLett.30.1343">'
             "doi:10.1103/PhysRevLett.30.1343</a>",
         )