add missing package_type header-library (#180)

* add missing package_type header-library

* Update tutorial/creating_packages/other_packages/header_only_gtest/conanfile.py

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Co-authored-by: Carlos Zoido <mrgalleta@gmail.com>

Author: memsharded

tutorial/creating_packages/other_packages/header_only/conanfile.py

@@ -8,6 +8,8 @@ class SumConan(ConanFile):
     # No settings/options are necessary, this is header only
     exports_sources = "include/*"
     no_copy_source = True
+    # Important, define the package_type
+    package_type = "header-library"
 
     def package(self):
         # This will also copy the "include" folder

tutorial/creating_packages/other_packages/header_only_gtest/conanfile.py

@@ -12,6 +12,8 @@ class SumConan(ConanFile):
     exports_sources = "include/*", "test/*"
     no_copy_source = True
     generators = "CMakeToolchain", "CMakeDeps"
+    # Important, define the package_type
+    package_type = "header-library"
 
     def validate(self):
         check_min_cppstd(self, 11)