chore: make apt-get instructions consistent and add GPG fingerprint (#…

…11326)

README.md

@@ -46,15 +46,18 @@ For deb-based platforms (e.g. Ubuntu and Debian) run the following to add the
 repo key and setup a new sources.list entry:
 
 ```shell
-wget -qO- https://repos.influxdata.com/influxdb.key | sudo tee /etc/apt/trusted.gpg.d/influxdata.asc >/dev/null
-echo "deb https://repos.influxdata.com/debian stable main" | sudo tee /etc/apt/sources.list.d/influxdata.list
+# influxdb.key GPG Fingerprint: 05CE15085FC09D18E99EFB22684A14CF2582E0C5
+wget -q https://repos.influxdata.com/influxdb.key
+echo '23a1c8836f0afc5ed24e0486339d7cc8f6790b83886c4c96995b88a061c5bb5d influxdb.key' | sha256sum -c && cat influxdb.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/influxdb.gpg > /dev/null
+echo 'deb [signed-by=/etc/apt/trusted.gpg.d/influxdb.gpg] https://repos.influxdata.com/debian stable main' | sudo tee /etc/apt/sources.list.d/influxdata.list
 sudo apt-get update && sudo apt-get install telegraf
 ```
 
 For RPM-based platforms (e.g. RHEL, CentOS) use the following to create a repo
 file and install telegraf:
 
 ```shell
+# influxdb.key GPG Fingerprint: 05CE15085FC09D18E99EFB22684A14CF2582E0C5
 cat <<EOF | sudo tee /etc/yum.repos.d/influxdata.repo
 [influxdata]
 name = InfluxData Repository - Stable