The colon equal sign regex should contain both colon and equal. Neither is optional. Specific for assignment and declaration in golang (#675)

Author: jpdakran

detect_secrets/plugins/keyword.py

@@ -98,7 +98,7 @@
 
 FOLLOWED_BY_COLON_EQUAL_SIGNS_REGEX = re.compile(
     # e.g. my_password := "bar" or my_password := bar
-    r'{denylist}({closing})?{whitespace}:=?{whitespace}({quote}?)({secret})(\3)'.format(
+    r'{denylist}({closing})?{whitespace}:={whitespace}({quote}?)({secret})(\3)'.format(
         denylist=DENYLIST_REGEX,
         closing=CLOSING,
         quote=QUOTE,

tests/plugins/keyword_test.py

@@ -83,6 +83,8 @@
     ('password := "somefakekey"', None),    # 'fake' in the secret
     ('some_key = "real_secret"', None),     # We cannot make 'key' a Keyword, too noisy)
     ('private_key "hopenobodyfindsthisone\';', None),  # Double-quote does not match single-quote)
+    ('password: real_key', None),
+    ('password: "real_key"', None),
     (LONG_LINE, None),  # Long line test
 ]