Add TruffleRuby 20.3.0

* It does not seem to work well.
* See https://github.com/actions/toolkit/issues/399

.github/workflows/test.yml

@@ -32,7 +32,6 @@ jobs:
         - { os: windows-2019, ruby: truffleruby }
         - { os: windows-2019, ruby: truffleruby-head }
         - { os: macos-11.0, ruby: truffleruby }
-        - { os: macos-11.0, ruby: truffleruby-head }
 
     name: ${{ matrix.os }} ${{ matrix.ruby }}
     runs-on: ${{ matrix.os }}
@@ -104,7 +103,7 @@ jobs:
       run: gem install sassc -N
 
   lint:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v2
     - run: yarn install

README.md

@@ -16,7 +16,7 @@ This action currently supports these versions of MRI, JRuby and TruffleRuby:
 | ----------- | -------- |
 | Ruby | 2.1.9, 2.2, 2.3.0 - 2.3.8, 2.4.0 - 2.4.10, 2.5.0 - 2.5.8, 2.6.0 - 2.6.6, 2.7.2, head, debug, mingw, mswin |
 | JRuby | 9.1.17.0, 9.2.9.0 - 9.2.13.0, head |
-| TruffleRuby | 19.3.0 - 20.2.0, head |
+| TruffleRuby | 19.3.0 - 20.3.0, head |
 
 `ruby-debug` is the same as `ruby-head` but with assertions enabled (`-DRUBY_DEBUG=1`).  
 On Windows, `mingw` and `mswin` are `ruby-head` builds using the MSYS2/MinGW and the MSVC toolchains respectively.
@@ -85,7 +85,6 @@ jobs:
         os: [ubuntu, macos]
         ruby: [2.5, 2.6, 2.7, head, debug, jruby, jruby-head, truffleruby, truffleruby-head]
     runs-on: ${{ matrix.os }}-latest
-    continue-on-error: ${{ endsWith(matrix.ruby, 'head') || matrix.ruby == 'debug' }}
     steps:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1

dist/index.js

@@ -44550,7 +44550,7 @@ function getVersions(platform) {
     ],
     "truffleruby": [
       "19.3.0", "19.3.1",
-      "20.0.0", "20.1.0", "20.2.0",
+      "20.0.0", "20.1.0", "20.2.0", "20.3.0",
       "head"
     ]
   }

ruby-builder-versions.js

@@ -18,7 +18,7 @@ export function getVersions(platform) {
     ],
     "truffleruby": [
       "19.3.0", "19.3.1",
-      "20.0.0", "20.1.0", "20.2.0",
+      "20.0.0", "20.1.0", "20.2.0", "20.3.0",
       "head"
     ]
   }