Fix condition that was missing after #26

This is especially usefull when a version line is contained
inside a yaml block

Signed-off-by: Frederic Martinsons <frederic.martinsons@sigfox.com>

tap2junit/tap13.py

@@ -107,7 +107,7 @@ def _parse(self, source):
             self.__tests_counter = 0
 
         for line in source:
-            if not version12 and not seek_version and RE_VERSION.match(line):
+            if not version12 and not seek_version and not in_yaml and RE_VERSION.match(line):
                 # refack: breaking TAP13 spec, to allow multiple TAP headers
                 seek_version = True
                 seek_plan = False