message: Fix "can be obtain" typo.
diff: @@ -218,7 +218,7 @@ directly in C++ code, one can use
  // use the keyset...
  ```
  -where `key_template` can be obtain from util classes corresponding to Tink primitives, e.g.
  +where `key_template` can be obtained from util classes corresponding to Tink primitives, e.g.
  [MacKeyTemplates](https://github.com/google/tink/blob/master/cc/mac/mac_key_templates.h),
  [AeadKeyTemplates](https://github.com/google/tink/blob/master/cc/aead/aead_key_templates.h),
  or
  