Revert "Temporarily disable the Toolchain plugin to facilitate landin…

…g Python 3.9 (pantsbuild#11466)"

This reverts commit a8c0f7b.

pants.toml

@@ -14,14 +14,14 @@ backend_packages.add = [
   "pants.backend.python.typecheck.mypy",
   "pants.backend.python.mixed_interpreter_constraints",
   "internal_plugins.releases",
-#  "toolchain.pants.auth",
-#  "toolchain.pants.buildsense",
-#  "toolchain.pants.common",
+  "toolchain.pants.auth",
+  "toolchain.pants.buildsense",
+  "toolchain.pants.common",
 ]
 
-#plugins = [
-#  "toolchain.pants.plugin==0.3.0",
-#]
+plugins = [
+  "toolchain.pants.plugin==0.3.0",
+]
 
 build_file_prelude_globs = ["pants-plugins/python_integration_tests_macro.py"]
 
@@ -142,5 +142,5 @@ interpreter_constraints = [">=3.7,<3.10"]
 [sourcefile-validation]
 config = "@build-support/regexes/config.yaml"
 
-#[toolchain-setup]
-#repo = "pants"
+[toolchain-setup]
+repo = "pants"

pants.travis-ci.toml

@@ -17,10 +17,10 @@ junit_xml_dir = "dist/test-results/"
 [coverage-py]
 report = ["raw", "xml"]
 
-#[auth]
-#from_env_var = "TOOLCHAIN_AUTH_TOKEN"
-#org = "pantsbuild"
-#ci_env_variables = ["TRAVIS", "TRAVIS_JOB_ID", "TRAVIS_BUILD_ID", "TRAVIS_PULL_REQUEST", "TRAVIS_BUILD_WEB_URL"]
-#
-#[buildsense]
-#enable = true
+[auth]
+from_env_var = "TOOLCHAIN_AUTH_TOKEN"
+org = "pantsbuild"
+ci_env_variables = ["TRAVIS", "TRAVIS_JOB_ID", "TRAVIS_BUILD_ID", "TRAVIS_PULL_REQUEST", "TRAVIS_BUILD_WEB_URL"]
+
+[buildsense]
+enable = true