Execlog parser should either prune or set a default for all the timing information.

Description of the bug:

Using something like:

> bazel-bin/src/tools/execlog/parser \
  --log_path=/Users/fzakaria/Documents/exec_protoc1.log \
  --log_path=/Users/fzakaria/Documents/exec_protoc2.log \
  --output_path=/tmp/exec1.log.txt \
  --output_path=/tmp/exec2.log.txt

I have included two compact exec logs to see how they are similar except for PATH and timings. Using diff tools produces many differences on account of the timings.

> diff /tmp/exec1.log.txt /tmp/exec2.log.txt | head -n 30
67c67
<   value: "/Users/fzakaria/Library/Caches/bazelisk/downloads/sha256/7dc88df4842a5b49830c55b174551445587ae60f027a67d0f847dbb35f1f40c6/bin:/Users/fzakaria/.pyenv/shims:/Users/fzakaria/.nix-profile/bin:/nix/var/nix/profiles/default/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/opt/homebrew/bin:/Applications/iTerm.app/Contents/Resources/utilities:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/access-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/cloud-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/connect-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/k8saas-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/devprod-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/traffic-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/ksql-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/orchestrator-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/kafka-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/servicefoundations-beta:/Users/fzakaria/.zsh/plugins/powerlevel10k"
---
>   value: "/Users/fzakaria/Library/Caches/bazelisk/downloads/sha256/7dc88df4842a5b49830c55b174551445587ae60f027a67d0f847dbb35f1f40c6/bin:/Users/fzakaria/.pyenv/shims:/Users/fzakaria/.nix-profile/bin:/nix/var/nix/profiles/default/bin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/opt/homebrew/bin:/Applications/iTerm.app/Contents/Resources/utilities:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/access-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/cloud-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/connect-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/k8saas-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/devprod-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/traffic-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/ksql-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/orchestrator-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/kafka-ga:/Users/fzakaria/code/github.com/confluentinc/cc-dotfiles/bin/servicefoundations-beta:/Users/fzakaria/.zsh/plugins/powerlevel10k:/bin2/"
568,569c568
< runner: "disk cache hit"
< cache_hit: true
---
> runner: "darwin-sandbox"
573c572
<   hash: "630a6822f70ec0fbb920b1ecfe78137657d6a46d989df99034b4f163913c7684"
---
>   hash: "c36a3b77ddd78a42d736c42c8c2ebb341548049db36a3e6591d440d8a004fc6b"
579c578
<     nanos: 8000000
---
>     nanos: 350000000
581,582c580,581
<   fetch_time {
<     nanos: 2000000
---
>   execution_wall_time {
>     nanos: 350000000
584,585d582
<   input_bytes: 1812815
<   input_files: 59
587,588c584,585
<     seconds: 1729717622
<     nanos: 557000000
---

exec_protoc2.log exec_protoc1.log

My vote would be for this to be the default, but I could imagine it needing to be behind a flag to retain original timings for whatever other workflows exist.