Empty tags

[vanderck]

Steps to reproduce

"tags":[],
will cause :

openapi:
Failed to generate files.
Bad state: No element
#0 List.first (dart:core-patch/growable_array.dart:344:5)
#1 OpenApiParser._getTag (package:swagger_parser/src/parser/parser/open_api_parser.dart:870:52)
#2 OpenApiParser.parseRestClients.. (package:swagger_parser/src/parser/parser/open_api_parser.dart:643:28)
#3 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:633:13)
#4 OpenApiParser.parseRestClients. (package:swagger_parser/src/parser/parser/open_api_parser.dart:567:17)
#5 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:633:13)
#6 OpenApiParser.parseRestClients (package:swagger_parser/src/parser/parser/open_api_parser.dart:554:10)
#7 GenProcessor.generateFiles (package:swagger_parser/src/generator/generator/generator_processor.dart:32:32)

Expected results

Just ignore empty tags

Actual results

Failed to generate files.
Bad state: No element

Your OpenApi snippet

"tags":[],

Code sample

Code sample

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Logs

Logs

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Dart version and used packages versions

Dart version

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Packages version

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