[spec] version_spec: forget about rev and commit (#4303)

Stable doesn't have them.

spec/unit/version_spec.lua

@@ -6,16 +6,12 @@ describe("Version module", function()
     end)
     it("should get current revision", function()
         local rev = Version:getCurrentRevision()
-        local year, month, revision = rev:match("v(%d%d%d%d)%.(%d%d)-?(%d*)")
-        local commit = rev:match("-%d*-g(%x*)[%d_%-]*")
+        local year, month, point, revision = rev:match("v(%d%d%d%d)%.(%d%d).?(%d?)-?(%d*)") -- luacheck: ignore 211
+        local commit = rev:match("-%d*-g(%x*)[%d_%-]*") -- luacheck: ignore 211
         assert.is_truthy(year)
         assert.is_truthy(month)
-        assert.is_truthy(revision)
-        assert.is_truthy(commit)
         assert.is_true(4 == year:len())
         assert.is_true(2 == month:len())
-        assert.is_true(1 <= revision:len())
-        assert.is_true(7 <= commit:len())
     end)
     it("should get normalized current version", function()
         assert.is_true(10 == tostring(Version:getNormalizedCurrentVersion()):len())