tink: grpc-server do not return error when creating bad template

Expected Behaviour

If one provides bad template to gRPC call to create a template, error should be returned.

Current Behaviour

Currently no error is returned, but no template is created either.

Steps to Reproduce (for bugs)

Add following unit test case:

diff --git grpc-server/template_test.go grpc-server/template_test.go
index 84fc6b3..fc67766 100644
--- grpc-server/template_test.go
+++ grpc-server/template_test.go
@@ -90,6 +90,18 @@ func TestCreateTemplate(t *testing.T) {
                                expectedError: true,
                        },
                },
+               "BadYAML": {
+                       args: args{
+                               db: mock.DB{
+                                       TemplateDB: make(map[string]interface{}),
+                               },
+                               name:     "template_1",
+                               template: `"foo`,
+                       },
+                       want: want{
+                               expectedError: true,
+                       },
+               },
        }

        for name := range testCases {

It can also be reproduced with tink CLI:

1. Create file bar.yaml with content: "foo (intentional not closed quote)
2. Run template create --name foo --path bar.yaml
3. Error should be returned.