Remove redundant `--template` arguments from code samples (#30909)
Remove redundant `--template` arguments from code samples (#30909)

This removes redundant --template arguments from the samples that I should have removed before in #30827 .

Also, fixed a bunch of spelling misteaks.
devoncarew/engine,devoncarew/engine,flutter/engine,flutter/engine,flutter/engine,jason-simmons/flutter_engine,jason-simmons/flutter_engine,jason-simmons/flutter_engine,chinmaygarde/flutter_engine,jason-simmons/flutter_engine,rmacnak-google/engine,rmacnak-google/engine,flutter/engine,jason-simmons/flutter_engine,flutter/engine,jason-simmons/flutter_engine,chinmaygarde/flutter_engine,rmacnak-google/engine,devoncarew/engine,devoncarew/engine,jason-simmons/flutter_engine,chinmaygarde/flutter_engine,devoncarew/engine,rmacnak-google/engine,jason-simmons/flutter_engine,chinmaygarde/flutter_engine,chinmaygarde/flutter_engine,flutter/engine,devoncarew/engine,flutter/engine,devoncarew/engine,rmacnak-google/engine,rmacnak-google/engine,rmacnak-google/engine,chinmaygarde/flutter_engine,flutter/engine,chinmaygarde/flutter_engine