update to golang 1.13.8

Signed-off-by: Mike Brown <brownwm@us.ibm.com>

.appveyor.yml

@@ -10,7 +10,7 @@ environment:
   CGO_ENABLED: 1
   GO111MODULE: off
   matrix:
-    - GO_VERSION: 1.13.4
+    - GO_VERSION: 1.13.8
 
 install:
   # Install Mingw

.travis.yml

@@ -3,7 +3,7 @@ git:
 
 language: go
 go:
-  - 1.13.4
+  - 1.13.8
   - tip
 
 

README.md

@@ -78,7 +78,7 @@ specifications as appropriate.
 backport version of `libseccomp-dev` is required. See [travis.yml](.travis.yml) for an example on trusty.
 * **btrfs development library.** Required by containerd btrfs support. `btrfs-tools`(Ubuntu, Debian) / `btrfs-progs-devel`(Fedora, CentOS, RHEL)
 2. Install **`socat`** (required by portforward).
-2. Install and setup a go 1.12.9 development environment. (Note: You can check the travis logs for a recent pull request to confirm the version(s) of golang currently being used to build and test master.)
+2. Install and setup a go 1.13.8 development environment. (Note: You can check the travis logs for a recent pull request to confirm the version(s) of golang currently being used to build and test master.)
 3. Make a local clone of this repository.
 4. Install binary dependencies by running the following command from your cloned `cri/` project directory:
 ```bash