feat: add ability to turn off provenance attestations

Lambda image functions don't support the Image Index artifact that's created when provenance set to true (which is buildx default). Need the ability to turn this off.

.github/workflows/reusable-docker-build.yml

@@ -54,6 +54,12 @@ on:
           e.g: |
               THING1=a
               THING2=b
+      provenance:
+        required: false
+        type: boolean
+        default: true
+        description: |
+          set to false to not create provenance attestations for the build process.
       platforms:
         required: false
         type: string
@@ -173,6 +179,7 @@ jobs:
           REGISTRY_GHCR_USERNAME_OVERRIDE: ${{ inputs.registryGhcrUsernameOverride }}
           TAGS: ${{ inputs.tags }}
           BUILD_ARGS: ${{ inputs.buildArgs }}
+          PROVENANCE: ${{ inputs.provenance }}
           PLATFORMS: ${{ inputs.platforms }}
           PUSH: ${{ inputs.push }}
           AWS_REGION: ${{ inputs.aws-region }}
@@ -312,6 +319,7 @@ jobs:
           platforms: ${{ steps.run-info.outputs.platforms }}
           file: ${{ inputs.dockerfile }}
           build-args: ${{ inputs.buildArgs }}
+          provenance: ${{ inputs.provenance }}
           labels: |
             org.opencontainers.image.name=${{ inputs.imageName }}
             org.opencontainers.image.revision=${{ github.sha }}