Fix comment

Signed-off-by: Takeshi Yoneda <[email protected]>

Author: mathetake

include/proxy-wasm/context.h

@@ -45,7 +45,8 @@ class WasmVm;
  * @param vm_id is a string used to differentiate VMs with the same code and VM configuration.
  * @param plugin_configuration is configuration for this plugin.
  * @param fail_open if true the plugin will pass traffic as opposed to close all streams.
- * @param key is for caching PluginBase per thread and deciding whether to create a new PluginBase.
+ * @param key is used for caching PluginBase per thread and determining whether to create a new
+ * PluginHandleBase.
  */
 struct PluginBase {
   PluginBase(std::string_view name, std::string_view root_id, std::string_view vm_id,