Issue title: Add to Raspbian package manager?
 Issue body: I tried to install this awesome project on a Raspberry Pi for a kiosk, but it doesn't seem to be available on the Raspberry Pi.

```
sudo apt-get install --no-install-recommends ungoogled-chromium -y
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package ungoogled-chromium
```

Could this project be added so that it can be easily installed?
 Comments: 
 Comment 0: The closest thing we have right now are [OBS builds](https://software.opensuse.org/download/package?package=ungoogled-chromium&project=home:ungoogled_chromium) (also linked in the README), which provides an APT repo. For ARM, OBS currently builds for armhf and arm64. Inclusion in Debian is an open issue: #27 

If I'm understanding you correctly, I think you're looking for inclusion in Debian. So, closing as a duplicate.
 Comment 1: Thanks for the quick reply.

I looked into OBS (for those finding this issue, it means "open build system", not "open broadcaster software"), but I couldn't for the life of me figure out how to use it to install Ungoogled Chromium. I suspected there must be an OBS client to install similar to APT. But I could find surprisingly little information about OBS.

I'm currently trying this approach:

```
echo ""
echo "Downloading the Ungoogled Chriomium browser"
sleep 2
wget https://download.opensuse.org/repositories/home:/ungoogled_chromium/Raspbian_Buster/armhf/ungoogled-chromium-common_81.0.4044.138-1.buster1_armhf.deb
wget https://download.opensuse.org/repositories/home:/ungoogled_chromium/Raspbian_Buster/armhf/ungoogled-chromium_81.0.4044.138-1.buster1_armhf.deb

echo ""
echo "Installing the Ungoogled Chriomium browser"
sleep 2
apt-get --no-install-recommends install ./ungoogled-chromium-common_81.0.4044.138-1.buster1_armhf.deb -y
apt-get --no-install-recommends install ./ungoogled-chromium_81.0.4044.138-1.buster1_armhf.deb -y

```

... and it's been installing for the past ten minutes (on a Pi 4). It seems to have to intall quite a bit:

```
Reading state information... Done
Note, selecting 'ungoogled-chromium' instead of './ungoogled-chromium_81.0.4044.138-1.buster1_armhf.deb'
The following additional packages will be installed:
  adwaita-icon-theme dconf-gsettings-backend dconf-service glib-networking glib-networking-common glib-networking-services
  gsettings-desktop-schemas gtk-update-icon-cache hicolor-icon-theme libatk-bridge2.0-0 libatk1.0-0 libatk1.0-data libatspi2.0-0
  libavahi-client3 libcairo-gobject2 libcolord2 libcups2 libdconf1 libgtk-3-0 libgtk-3-common libjson-glib-1.0-0
  libjson-glib-1.0-common libjsoncpp1 liblcms2-2 libminizip1 libnspr4 libnss3 libproxy1v5 libre2-5 librest-0.7-0 libsoup-gnome2.4-1
  libsoup2.4-1 libwebpdemux2 libxslt1.1
Suggested packages:
  colord cups-common gvfs liblcms2-utils ungoogled-chromium-l10n ungoogled-chromium-shell ungoogled-chromium-driver
Recommended packages:
  at-spi2-core libgtk-3-bin ungoogled-chromium-sandbox
The following NEW packages will be installed:
  adwaita-icon-theme dconf-gsettings-backend dconf-service glib-networking glib-networking-common glib-networking-services
  gsettings-desktop-schemas gtk-update-icon-cache hicolor-icon-theme libatk-bridge2.0-0 libatk1.0-0 libatk1.0-data libatspi2.0-0
  libavahi-client3 libcairo-gobject2 libcolord2 libcups2 libdconf1 libgtk-3-0 libgtk-3-common libjson-glib-1.0-0
  libjson-glib-1.0-common libjsoncpp1 liblcms2-2 libminizip1 libnspr4 libnss3 libproxy1v5 libre2-5 librest-0.7-0 libsoup-gnome2.4-1
  libsoup2.4-1 libwebpdemux2 libxslt1.1 ungoogled-chromium
0 upgraded, 35 newly installed, 0 to remove and 63 not upgraded.
```
 Comment 2: > OBS client to install similar to APT

What are you talking about? The link from README (which Eloston had provided in his comment above) has a section with instructions on how to add this repository to your Debian or Ubuntu system.
Quote from there:
```
echo 'deb http://download.opensuse.org/repositories/home:/ungoogled_chromium/Raspbian_Buster/ /' | sudo tee /etc/apt/sources.list.d/home:ungoogled_chromium.list
sudo wget -nv https://download.opensuse.org/repositories/home:ungoogled_chromium/Raspbian_Buster/Release.key -O "/etc/apt/trusted.gpg.d/home:ungoogled_chromium.asc"
sudo apt update
sudo apt install ungoogled-chromium
```
{'source': 'GithubIssues', 'repo_name_with_owner': 'Eloston/ungoogled-chromium', 'issue_id': 628591120, 'repo_stars': 15534.0}