update R build and test script in petstore samples

Author: wing328

samples/client/petstore/R-httr2-wrapper/build_and_test.bash

@@ -23,4 +23,4 @@ rm petstore_1.0.0.tar.gz || true
 
 R CMD build .
 R CMD check *tar.gz --no-manual
-R CMD install --preclean *tar.gz
+R CMD INSTALL --preclean *tar.gz

samples/client/petstore/R-httr2/build_and_test.bash

@@ -23,4 +23,4 @@ rm petstore_1.0.0.tar.gz || true
 
 R CMD build .
 R CMD check *tar.gz --no-manual
-R CMD install --preclean *tar.gz
+R CMD INSTALL --preclean *tar.gz

samples/client/petstore/R/build_and_test.bash

@@ -25,4 +25,4 @@ rm petstore_1.0.0.tar.gz || true
 
 R CMD build .
 R CMD check *tar.gz --no-manual
-R CMD install --preclean *tar.gz
+R CMD INSTALL --preclean *tar.gz