Updating bazel package: get right sha256 sum

Hi,

I’m trying to update https://github.com/NixOS/nixpkgs/tree/master/pkgs/servers/http/envoy . I’m not sure how the get the right sha256 sum for the attribute of fetchAttrs.sha256. I thought if I insert a wrong sha I will see the expectetd one in the error message. But trying to build it I only get:

INFO: Found 1 target...

INFO: Elapsed time: 303.026s

INFO: 0 processes.

INFO: Build completed successfully, 0 total actions
INFO: Build completed successfully, 0 total actions
@nix { "action": "setPhase", "phase": "installPhase" }
installing
builder for '/nix/store/f9b8za1qnnrfc2rmb77a9yyn2518wvxg-envoy-1.17.1-deps.tar.gz.drv' failed with exit code 1
error: build of '/nix/store/f9b8za1qnnrfc2rmb77a9yyn2518wvxg-envoy-1.17.1-deps.tar.gz.drv' failed

I was grepping for error in the output. Grepping for debug gives this messages.

DEBUG: /build/output/external/bazel_toolchains/rules/rbe_repo/version_check.bzl:68:14:
Current running Bazel is ahead of bazel-toolchains repo. Please update your pin to bazel-toolchains repo in your WORKSPACE file.
Loading: 0 packages loaded
DEBUG: /build/output/external/bazel_toolchains/rules/rbe_repo/version_check.bzl:68:14:
Current running Bazel is ahead of bazel-toolchains repo. Please update your pin to bazel-toolchains repo in your WORKSPACE file.
Loading: 0 packages loaded
DEBUG: /build/output/external/bazel_toolchains/rules/rbe_repo/version_check.bzl:68:14:
Current running Bazel is ahead of bazel-toolchains repo. Please update your pin to bazel-toolchains repo in your WORKSPACE file.
Loading: 0 packages loaded
DEBUG: /build/output/external/bazel_toolchains/rules/rbe_repo/version_check.bzl:68:14:
Current running Bazel is ahead of bazel-toolchains repo. Please update your pin to bazel-toolchains repo in your WORKSPACE file.
Loading: 0 packages loaded
DEBUG: /build/output/external/bazel_toolchains/rules/rbe_repo/version_check.bzl:68:14:
Current running Bazel is ahead of bazel-toolchains repo. Please update your pin to bazel-toolchains repo in your WORKSPACE file.
Loading: 0 packages loaded
Loading: 0 packages loaded
    currently loading: source/exe
--
DEBUG: /build/output/external/bazel_gazelle/internal/go_repository.bzl:189:18: com_github_lyft_protoc_gen_star: gazelle: finding module path for import github.com/stretchr/testify/assert: exit status 1: go: invalid module path "gazelle_remote_cache__\\n": contains disallowed shell character '\\'
gazelle: finding module path for import github.com/stretchr/testify/require: exit status 1: go: invalid module path "gazelle_remote_cache__\\n": contains disallowed shell character '\\'
gazelle: finding module path for import github.com/spf13/afero: exit status 1: go: invalid module path "gazelle_remote_cache__\\n": contains disallowed shell character '\\'
gazelle: finding module path for import github.com/spf13/afero: exit status 1: go: invalid module path "gazelle_remote_cache__\\n": contains disallowed shell character '\\'
gazelle: finding module path for import github.com/stretchr/testify/assert: exit status 1: go: invalid module path "gazelle_remote_cache__\\n": contains disallowed shell character '\\'