atlasaction: base64url encoding for plan's filename #1026

Job	Run time
golangci-lint	17s
migrate-down	26s
migrate-test	18s
schema-apply (lint-review)	16s
schema-plan	15s
schema-plan-approve	0s
schema-apply (on-the-fly, true)	14s
schema-apply (remote-repo, atlas://atlas-action/plans/20240910183610, atlas://atlas-action?tag=e2e)	14s
schema-apply (local-plan, file://20240910173744.plan.hcl)	16s
schema-push	14s
schema-test	15s
schema-apply (multiple-envs, file://20240910173744.plan.hcl)	14s
schema-apply (legacy, v0.27.0, true)	14s
shim	15s
shim-e2e	12s
unit-tests	1m 14s
	4m 54s

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