[R-package] add some R build files to gitignore (#3271)

.gitignore

@@ -400,8 +400,10 @@ python-package/lightgbm/VERSION.txt
 
 # R build artefacts
 **/autom4te.cache/
+R-package/config.status
 R-package/docs
 R-package/src/CMakeLists.txt
+R-package/src/Makevars
 R-package/src/lib_lightgbm.so.dSYM/
 R-package/src/src/
 R-package/src-x64
@@ -410,6 +412,7 @@ R-package/**/VERSION.txt
 **/Makevars.win
 lightgbm_r/*
 lightgbm*.tar.gz
+lightgbm*.tgz
 lightgbm.Rcheck/
 miktex*.zip
 *.def