nit: Fix tabs vs spaces

Dockerfile

@@ -4,17 +4,17 @@ LABEL Description="Use the Balena CLI to perform actions"
 # Install the standalone balena-cli package
 RUN apt-get update && apt-get install -y \
     curl \
-	unzip && \
+    unzip && \
   cd /opt/ && \
   curl -s https://api.github.com/repos/balena-io/balena-cli/releases/latest | \
     grep browser_download_url.*balena-cli-v.*-linux-x64-standalone.zip | \
-	cut -d : -f 2,3 | \
-	xargs -n 1 curl -O -sSL && \
+    cut -d : -f 2,3 | \
+    xargs -n 1 curl -O -sSL && \
   unzip balena-cli-*-linux-x64-standalone.zip && \
   ln -s /opt/balena-cli/balena /usr/bin/ && \
   apt-get purge -y \
     curl \
-	unzip && \
+    unzip && \
   apt-get autoremove -y && \
   rm -rf \
     balena-cli-*-linux-x64-standalone.zip \