Error on installation in iobroker.ham 
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### What issue do you have? Please be as thorough and explicit as possible.

In iobroker.ham the installation of homebridge-ewelink fails with an error 

ERR! notsup Unsupported engine for homebridge-ewelink@3.15.0: wanted: {"homebridge":"^1.1.0","node":"^14.15.1"} (current: {"node":"12.20.0","npm":"6.14.8"}) npm ERR! notsup Not compatible with


### Details of your setup.
* Do you use Homebridge (with config-ui?) or HOOBS? 
Homebridge HAM in iobroker 



* Which version of Homebridge/HOOBS do you have?
HAM in version 3.2 

* Which version of this plugin (homebridge-ewelink) do you have? Has the issue started since upgrading from a previous version?

v3.15.0 

* Do you use your main eWeLink credentials or do you use a secondary eWeLink account for Homebridge?
 
Main credentials 


### Please paste any relevant logs below.
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