Update .travis.yml

Author: ImVexed

.travis.yml

@@ -7,7 +7,7 @@ language: go
 # You don't need to test on very old version of the Go compiler. It's the user's
 # responsibility to keep their compilers up to date.
 go:
-  - 1.12.x
+  - 1.18beta1
 
 # Only clone the most recent commit.
 git:
@@ -29,4 +29,4 @@ before_script:
 # .golangci.yml file at the top level of your repo.
 script:
   - golangci-lint run       # run a bunch of code checkers/linters in parallel
-  - go test -v -race ./...  # Run all the tests with the race detector enabled
+  - go test -v -race ./...  # Run all the tests with the race detector enabled