Utilizar rotas do Build do React em servidor Apache ou IIS

.htaccess

RewriteEngine On

RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^ index.html [QSA,L]

web.config

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <system.webServer>
        <rewrite>
            <rules>
                <rule name="Imported Rule 1" stopProcessing="true">
                    <match url="^" ignoreCase="false" />
                    <conditions logicalGrouping="MatchAll">
                        <add input="{REQUEST_FILENAME}" matchType="IsFile" ignoreCase="false" negate="true" />
                    </conditions>
                    <action type="Rewrite" url="index.html" appendQueryString="true" />
                </rule>
            </rules>
        </rewrite>
    </system.webServer>
    <system.web>
        <customErrors mode="On" />
    </system.web>
</configuration>