I cant upload files to zeroup

### Step 1: Please describe your environment

* ZeroNet version: 0.7.2 (rev4555)
* Operating system: Windows 10 Pro
* Web browser: Google Chrome
* Tor status: available
* Opened port: yes
* Special configuration: none

### Step 2: Describe the problem:
I'm getting this error: Site sign failed: data/users/1AkCd6161a4erMEbe4998aX7Hnpd2iuEMu/content.json: VerifyError: Include optional files too large 1097575909B > 1000000000B in /src/Ui/UiWebsocket.py line 446 >
#### Steps to reproduce:

1. try to upload a file

#### Observed Results:

Site sign failed: data/users/1AkCd6161a4erMEbe4998aX7Hnpd2iuEMu/content.json: VerifyError: Include optional files too large 1097575909B > 1000000000B in /src/Ui/UiWebsocket.py line 446 >

#### Expected Results:

just upload the file

Start at core/src/Ui/UiWebsocket.py line 446 and reproduce the upload flow using the reported ZeroNet 0.7.2 environment and error. Trace how the optional-file size is checked when signing content.json. Done means the reported file-upload case is handled as intended without the Site sign failed error.

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