integration with digitalocean spaces

[benitogf]

currently I'm not able to use tusd with digitalocean (s3 compatible service) spaces

To Reproduce

I'm using this systemd service file to run tusd:

[Install]
WantedBy=default.target

[Unit]
Description=tusd service
After=syslog.target network.target multi-user.target

[Service]
Environment="AWS_ACCESS_KEY_ID={DO_ACCESS_KEY}"
Environment="AWS_SECRET_ACCESS_KEY={DO_SECRET_KEY}"
Environment="AWS_REGION=us-east-1"
ExecStart=/usr/bin/tusd -host="127.0.0.1" -s3-bucket="{DO_SPACE_NAME}" -s3-endpoint="{DO_SPACE_ENDPOINT}"
Restart=always
RestartSec=1

able to upload files, but fetch fails with 500 (NoSuchKey) error

Setup details
Please provide following details, if applicable to your situation:

• Operating System: Ubuntu 20.04
• Used tusd version: v1.6.0
• Used tusd data storage: digital ocean spaces (s3)
• Used tusd configuration: s3-bucket and s3-endpoint
• Used tus client library: tus-js-client

[Acconut]

Closing in favor the proposed PR #507.