Fix some typos in the English locale (fixes #4663) (#4793)

webapp/components/help/components/commands.jsx

@@ -17,7 +17,7 @@ export default class HelpCommands extends React.Component {
         message.push('![commands](https://docs.mattermost.com/_images/slashCommandsTable1.PNG)');
         message.push(localizeMessage('help.commands.builtin2', 'Begin by typing `/` and a list of slash command options appears above the text input box. The autocomplete suggestions help by providing a format example in black text and a short description of the slash command in grey text.'));
         message.push('![autocomplete](https://docs.mattermost.com/_images/slashCommandsAutocomplete.PNG)');
-        message.push(localizeMessage('help.commands.custom', '## Custom Commands\nCustom slash commands integrate with external applications. For example, a team might configure a custom slash command to check internal health records with `/patient joe smith` or check the weekly weather forcast in a city with `/weather toronto week`. Check with your System Admin or open the autocomplete list by typing `/` to determine if your team configured any custom slash commands.'));
+        message.push(localizeMessage('help.commands.custom', '## Custom Commands\nCustom slash commands integrate with external applications. For example, a team might configure a custom slash command to check internal health records with `/patient joe smith` or check the weekly weather forecast in a city with `/weather toronto week`. Check with your System Admin or open the autocomplete list by typing `/` to determine if your team configured any custom slash commands.'));
         message.push(localizeMessage('help.commands.custom2', 'Custom slash commands are disabled by default and can be enabled by the System Admin in the **System Console** > **Integrations** > **Webhooks and Commands**. Learn about configuring custom slash commands on the [developer slash command documentation page](http://docs.mattermost.com/developer/slash-commands.html).'));
 
         return (