Fix reverse dependency core Updater -> library ESP8266WiFi (#6398)

* Per @earlephilhower suggestion

* Hints from @earlephilhower

* Namespace BearSSL in core "feels" wrong - using catch-all esp8266 instead.

* After review remarks by @earlephilhower

libraries/ESP8266WiFi/src/BearSSLHelpers.h

@@ -26,7 +26,6 @@
 #include <bearssl/bearssl.h>
 #include <Updater.h>
 
-
 // Internal opaque structures, not needed by user applications
 namespace brssl {
   class public_key;