[fork] Generate GDB backtraces in fork tests on Kokoro (#32535)

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templates/tools/dockerfile/test/bazel/Dockerfile.template

@@ -17,6 +17,8 @@
   <%include file="../../oss_fuzz_base.include"/>
   <%include file="../../bazel.include"/>
   <%include file="../../git-jenkins.include"/>
+
+  RUN apt-get install -y gdb
   
   RUN mkdir -p /var/local/jenkins
 

tools/dockerfile/test/bazel.current_version

@@ -1 +1 @@
-us-docker.pkg.dev/grpc-testing/testing-images-public/bazel:b3e48464a04576cc42dd4f946feaf4fec1eca447@sha256:1faf10ff176c391507a5a4ed7b0c513d95bcd9f5a71877796d00a48039a67f55
+us-docker.pkg.dev/grpc-testing/testing-images-public/bazel:b7cb23cf132daefa62a7a108271528dea0c45403@sha256:8c31d465e58102b259274f38dd688e3b570682940fa05dea1cf1b10abca02a0b

tools/dockerfile/test/bazel/Dockerfile

@@ -64,6 +64,8 @@ RUN git config --global --add safe.directory /var/local/jenkins/grpc
 RUN git config --global protocol.file.allow always
 
 
+RUN apt-get install -y gdb
+
 RUN mkdir -p /var/local/jenkins
 
 # Define the default command.

tools/internal_ci/helper_scripts/prepare_build_linux_rc

@@ -40,6 +40,10 @@ git submodule update --init
 
 python3 -m pip install six
 
+# Allows the test driver to spin up a GDB subprocess and have it attach to
+# another subprocess of the test driver.
+sudo bash -c 'echo "0" > /proc/sys/kernel/yama/ptrace_scope'
+
 # check whether /tmpfs is mounted correctly
 (mount | grep -q 'on /tmpfs ') || (mount; echo 'BAD KOKORO WORKER WARNING: it seems that /tmpfs volume with scratch disk is not mounted in the kokoro worker. This can result in unexpected "out of disk space" errors.')