Remove obsolete .gitmodules files (#36)

packages/app-shell/.gitmodules

-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git
-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common
-[submodule "vendor/notification"]
-	path = vendor/notification
-	url = git@gitlab.tugraz.at:dbp/web-components/Notification
-[submodule "vendor/language-select"]
-	path = vendor/language-select
-	url = git@gitlab.tugraz.at:dbp/web-components/LanguageSelect
-[submodule "vendor/person-profile"]
-	path = vendor/person-profile
-	url = git@gitlab.tugraz.at:dbp/web-components/PersonProfile

packages/data-table-view/.gitmodules

-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git
-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git

packages/knowledge-base-web-page-element-view/.gitmodules

-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git
-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git

packages/language-select/.gitmodules

-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git

packages/matomo/.gitmodules

-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git
-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git

packages/notification/.gitmodules

-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git

packages/person-profile/.gitmodules

-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git
-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git
-[submodule "vendor/person-select"]
-	path = vendor/person-select
-	url = git@gitlab.tugraz.at:dbp/web-components/PersonSelect.git

packages/person-select/.gitmodules

-[submodule "vendor/auth"]
-	path = vendor/auth
-	url = git@gitlab.tugraz.at:dbp/web-components/Auth.git
-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git

packages/qr-code-scanner/.gitmodules

-[submodule "vendor/common"]
-	path = vendor/common
-	url = git@gitlab.tugraz.at:dbp/web-components/Common.git