[test] Use permalinks for ArtifactInstallation artifacts (#4240)

Author: giordano

test/test_packages/ArtifactInstallation/Artifacts.toml

@@ -147,16 +147,16 @@ git-tree-sha1 = "43563e7631a7eafae1f9f8d9d332e3de44ad7239"
 lazy = true
 
 [[socrates.download]]
-url = "https://github.com/staticfloat/small_bin/raw/master/socrates.tar.gz"
+url = "https://github.com/staticfloat/small_bin/raw/91f3ecf327d1de943fe076657833252791ba9f60/socrates.tar.gz"
 sha256 = "e65d2f13f2085f2c279830e863292312a72930fee5ba3c792b14c33ce5c5cc58"
 
 [[socrates.download]]
-url = "https://github.com/staticfloat/small_bin/raw/master/socrates.tar.bz2"
+url = "https://github.com/staticfloat/small_bin/raw/91f3ecf327d1de943fe076657833252791ba9f60/socrates.tar.bz2"
 sha256 = "13fc17b97be41763b02cbb80e9d048302cec3bd3d446c2ed6e8210bddcd3ac76"
 
 [collapse_the_symlink]
 git-tree-sha1 = "69a468bd51751f4ed7eda31c240e775df06d6ee6"
 
 [[collapse_the_symlink.download]]
-url = "https://github.com/staticfloat/small_bin/raw/master/collapse_the_symlink/collapse_the_symlink.tar.gz"
+url = "https://github.com/staticfloat/small_bin/raw/91f3ecf327d1de943fe076657833252791ba9f60/collapse_the_symlink/collapse_the_symlink.tar.gz"
 sha256 = "956c1201405f64d3465cc28cb0dec9d63c11a08cad28c381e13bb22e1fc469d3"