is "" a better default

action.yml

@@ -8,12 +8,12 @@ inputs:
     required: true
   environment:
     description: "Environment to run the command in. If not specified it will try to find local Flox environment."
-    default: null
+    default: ""
 
 runs:
   using: "composite"
   steps:
     # TODO: automatically login to floxhub if not logged in already and FLOX_TOKEN is present
     - name: "Run flox activate"
       shell: "bash"
-      run: "flox activate ${{ inputs.environment == null && '' || format('--remote={0}', inputs.environment) }} -- ${{ inputs.command }}"
+      run: "flox activate ${{ inputs.environment == '' && '' || format('--remote={0}', inputs.environment) }} -- ${{ inputs.command }}"