Work around importing the deprecated the imp module in Verify TLS configuration (#3978)

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---------

Co-authored-by: Landon James <lnj@amazon.com>

Author: ysaito1001

.github/workflows/ci-tls.yml

@@ -19,7 +19,10 @@ on:
 jobs:
   verify-tls-config:
     name: Verify TLS configuration
-    runs-on: ubuntu-latest
+    # TODO: GH runners recently bumped the default Ubuntu version to 24.x, this comes with an upgraded OpenSSL
+    # version that causes the python oscrypto package to throw an error: https://github.com/wbond/oscrypto/issues/78
+    # Until that package is updated we are pinning the version here.
+    runs-on: ubuntu-22.04
     timeout-minutes: 20
     steps:
     - name: Install packages

tools/ci-scripts/configure-tls/configure-trytls

@@ -7,6 +7,12 @@
 set -euxo pipefail
 
 perl -p -i -e 's!\./runners!runners!' setup.py
+
+sed -i 's/^import imp$/import importlib/' setup.py
+sed -i 's/^found = imp.find_module.*/sys.path.insert(0, os.path.join(os.path.dirname(__file__), "runners"))\
+found = importlib.util.find_spec("trytls")/' setup.py
+sed -i 's/^trytls = imp.load_module(\(.*\))$/trytls = importlib.util.module_from_spec(found)\nfound.loader.exec_module(trytls)/' setup.py
+
 sed -i '/import platform/a import distro' runners/trytls/utils.py
 sed -i 's/platform.linux_distribution()/distro.name(), distro.version(), distro.id()/' runners/trytls/utils.py
 sed -i 's/break//' runners/trytls/bundles/https.py