Add -O2 copt to release config

[pudelkoM]

Currently we append a special bazelrc file for CI runs. It overrides the compiler optimization level with -O0. This is not suitable for release builds. Therefore we add the copt for release builds explicitly.

fixes #891

[pudelkoM]

Invocation with -O2 last:

/usr/bin/clang -U_FORTIFY_SOURCE -fstack-protector -Wall -Wthread-safety -Wself-assign -Wno-free-nonheap-object -fcolor-diagnostics -fno-omit-frame-pointer -g0 -O2 '-D_FORTIFY_SOURCE=1' -DNDEBUG -ffunction-sections -fdata-sections '-std=c++0x' -MD -MF bazel-out/k8-opt/bin/external/com_github_openconfig_hercules/_objs/openconfig_proto/openconfig.pb.d '-frandom-seed=bazel-out/k8-opt/bin/external/com_github_openconfig_hercules/_objs/openconfig_proto/openconfig.pb.o' -iquote external/com_github_openconfig_hercules -iquote bazel-out/k8-opt/bin/external/com_github_openconfig_hercules -iquote external/com_google_protobuf -iquote bazel-out/k8-opt/bin/external/com_google_protobuf -iquote external/zlib -iquote bazel-out/k8-opt/bin/external/zlib -iquote external/com_github_openconfig_ygot_proto -iquote bazel-out/k8-opt/bin/external/com_github_openconfig_ygot_proto -Ibazel-out/k8-opt/bin/external/com_github_openconfig_hercules/_virtual_includes/openconfig_proto -Ibazel-out/k8-opt/bin/external/com_github_openconfig_ygot_proto/_virtual_includes/yext_proto -Ibazel-out/k8-opt/bin/external/com_google_protobuf/_virtual_includes/descriptor_proto -Ibazel-out/k8-opt/bin/external/com_github_openconfig_ygot_proto/_virtual_includes/ywrapper_proto -Ibazel-out/k8-opt/bin/external/com_google_protobuf/_virtual_includes/any_proto -isystem external/com_google_protobuf/src -isystem bazel-out/k8-opt/bin/external/com_google_protobuf/src -isystem external/zlib -isystem bazel-out/k8-opt/bin/external/zlib -O0 -O2 '-std=gnu++11' -no-canonical-prefixes -Wno-builtin-macro-redefined '-D__DATE__="redacted"' '-D__TIMESTAMP__="redacted"' '-D__TIME__="redacted"' -c bazel-out/k8-opt/bin/external/com_github_openconfig_hercules/_virtual_imports/openconfig_proto/openconfig/openconfig.pb.cc -o bazel-out/k8-opt/bin/external/com_github_openconfig_hercules/_objs/openconfig_proto/openconfig.pb.o

[codecov]

Codecov Report

Merging #893 (f849d74) into main (4be1639) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #893   +/-   ##
=======================================
  Coverage   78.80%   78.80%           
=======================================
  Files         336      336           
  Lines       30128    30128           
=======================================
  Hits        23742    23742           
  Misses       6386     6386