Fix go fmt issues

[kbespalov]

The make fmtcheck fails with the following error:

1. fmtcheck output

kbespalov@home-pc:~/workspaces/terraform-provider-yandex$ make fmtcheck
==> Checking that code complies with gofmt requirements...
gofmt needs running on the following files:
./yandex/internal/mutexkv/mutexkv.go
./yandex/resource_yandex_storage_bucket_test.go
./yandex/resource_yandex_storage_bucket.go
You can use the command: `make fmt` to reformat code.
make: *** [GNUmakefile:42: fmtcheck] Error 1
kbespalov@home-pc:~/workspaces/terraform-provider-yand

2. go fmt output

 gofmt -d -l .
yandex/internal/mutexkv/mutexkv.go
diff yandex/internal/mutexkv/mutexkv.go.orig yandex/internal/mutexkv/mutexkv.go
--- yandex/internal/mutexkv/mutexkv.go.orig
+++ yandex/internal/mutexkv/mutexkv.go
@@ -8,7 +8,6 @@
 // MutexKV is a simple key/value store for arbitrary mutexes. It can be used to
 // serialize changes across arbitrary collaborators that share knowledge of the
 // keys they must serialize on.
-//
 type MutexKV struct {
        lock  sync.Mutex
        store map[string]*sync.Mutex
yandex/resource_yandex_storage_bucket.go
diff yandex/resource_yandex_storage_bucket.go.orig yandex/resource_yandex_storage_bucket.go
--- yandex/resource_yandex_storage_bucket.go.orig
+++ yandex/resource_yandex_storage_bucket.go
@@ -1904,9 +1904,9 @@
 }
 
 // Returns true if the error matches all these conditions:
-//  * err is of type awserr.Error
-//  * Error.Code() matches code
-//  * Error.Message() contains message
+//   - err is of type awserr.Error
+//   - Error.Code() matches code
+//   - Error.Message() contains message
 func isAWSErr(err error, code string, message string) bool {
        if err, ok := err.(awserr.Error); ok {
                return err.Code() == code && strings.Contains(err.Message(), message)
yandex/resource_yandex_storage_bucket_test.go
diff yandex/resource_yandex_storage_bucket_test.go.orig yandex/resource_yandex_storage_bucket_test.go
--- yandex/resource_yandex_storage_bucket_test.go.orig
+++ yandex/resource_yandex_storage_bucket_test.go
@@ -1199,7 +1199,7 @@
        }
 }

[apilikov]

I've run this locally with latest master and don't see any issues. Do you still experience the same problems?