Fix ThriftyLib 2027 alpha jsonUrl

jsonUrl pointed at the /software/thriftylib folder, which redirects to
the docs page. check.py calls json.load() on the response and only
catches HTTPError, so the HTML surfaced as an uncaught JSONDecodeError
and both tests failed on every PR to this repo.

Point at the explicit file, which already serves the vendordep JSON.

Author: joelmuyskens

2027_alpha5/ThriftyLib-2027.0.0-alpha-1.json

@@ -7,7 +7,7 @@
     "mavenUrls": [
         "https://docs.home.thethriftybot.com"
     ],
-    "jsonUrl": "https://docs.home.thethriftybot.com/software/thriftylib",
+    "jsonUrl": "https://docs.home.thethriftybot.com/software/thriftylib/ThriftyLib.json",
     "javaDependencies": [
         {
             "groupId": "com.thrifty.frc",

2027_alpha5/ThriftyLib-2027.0.0-alpha-2.json

@@ -7,7 +7,7 @@
     "mavenUrls": [
         "https://docs.home.thethriftybot.com"
     ],
-    "jsonUrl": "https://docs.home.thethriftybot.com/software/thriftylib",
+    "jsonUrl": "https://docs.home.thethriftybot.com/software/thriftylib/ThriftyLib.json",
     "javaDependencies": [
         {
             "groupId": "com.thrifty.frc",