Fix: remove Spectra.jl from docs/Project.toml

Author: aditya-pandey-dev

docs/Project.toml

@@ -13,7 +13,6 @@ Measurements = "eff96d63-e80a-5855-80a2-b1b0885c5ab7"
 MultiDocumenter = "87ed4bf0-c935-4a67-83c3-2a03bee4197c"
 Plots = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 Revise = "295af30f-e4ad-537b-8983-00126c2a3abe"
-Spectra = "391af1a9-06f1-59d3-8d21-0be089654739"
 Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 UnitfulAstro = "6112ee07-acf9-5e0f-b108-d242c714bf9f"