uprev golang to 1.14.9

1.14 had a bug in the checkptr code (well, not exactly a bug) which
made it enforce alignment requirements on x86. This turns out not
to be the problem I was seeing, but we should be on 1.14.9 anyway.

To keep this from breaking CI integration with Github, we also
use explicit job names instead of matrix-generated ones, and fix
the CI config syntax up a bit after almost getting that right the
first try. (This patch includes fixes contributed by Cody, and since
I had to rebase and re-approve AGAIN anyway, I might as well squash
the commit history up.)

.circleci/config.yml

@@ -5,7 +5,7 @@ executors:
     parameters:
       version:
         type: string
-        default: "1.14"
+        default: "1.14.9"
       resource_class:
         type: string
         default: medium
@@ -84,7 +84,7 @@ jobs:
         default: medium
       golang_version:
         type: string
-        default: "1.14"
+        default: "1.14.9"
       shard_width:
         type: string
         default: "20"
@@ -192,16 +192,31 @@ workflows:
           requires:
             - setup
       - test:
-          name: test-golang-<< matrix.golang_version >>
-          matrix:
-            parameters:
-              golang_version: ["1.14", "1.13"]
+          name: test-golang-1.13
           resource_class: xlarge
+          golang_version: 1.13.15
           requires:
             - setup
           filters:
             tags:
               only: /^v.*/
+      - test:
+          name: test-golang-1.14
+          resource_class: xlarge
+          golang_version: 1.14.9
+          requires:
+            - setup
+          filters:
+            tags:
+              only: /^v.*/
+      # Ideally we would do something like the following instead of the above,
+      # but we don't like having point releases in the CI run name. Maybe in
+      # the future we can go back to this:
+      #- test:
+      #  name: test-golang-<< matrix.golang_version >>
+      #  matrix:
+      #    parameters:
+      #      golang_version: ["1.14.9", "1.13.15"]
       - test:
           name: test-race
           test_make_target: test-race