Fix forced lowercase username in login/registration flows (#9329)

* remove lowercase (proposal)

Lowercase doesn't make sense here (at least in German). I suggest removing it or creating a new translatable string.

* remove lowercase

Lowercase doesn't make sense here (at least in German). I suggest removing it or creating a new translatable string.

* Update screenshot

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Co-authored-by: David Baker <dbkr@users.noreply.github.com>

src/components/views/auth/PasswordLogin.tsx

@@ -310,7 +310,7 @@ export default class PasswordLogin extends React.PureComponent<IProps, IState> {
                         key="username_input"
                         type="text"
                         label={_t("common|username")}
-                        placeholder={_t("common|username").toLocaleLowerCase()}
+                        placeholder={_t("common|username")}
                         value={this.props.username}
                         onChange={this.onUsernameChanged}
                         onBlur={this.onUsernameBlur}

src/components/views/auth/RegistrationForm.tsx

@@ -530,7 +530,7 @@ export default class RegistrationForm extends React.PureComponent<IProps, IState
                 type="text"
                 autoFocus={true}
                 label={_t("common|username")}
-                placeholder={_t("common|username").toLocaleLowerCase()}
+                placeholder={_t("common|username")}
                 value={this.state.username}
                 onChange={this.onUsernameChange}
                 onValidate={this.onUsernameValidate}