fix: Helm Docs makefile to be compatible with macOs

[ishuar]

• Currently Documentation/Makefile is using $(QUIET)$(SED) 's/^\( \* - \)\([[:print:]]\+\)$$/\1:spelling:ignore:\2/' $@ > $(TMP_FILE_3) where sed has incompatible syntax in macOS. This does not add :spelling:ignore: string in between the $1 and $2 capture groups.

More detailed discussion took place at:

• Feat: enable securityContext on spire server pod #27363 (comment)

docs: Fix Documentation Makefile to make Helm reference updates compatible with macOS

Fixes: #27122
Fixes: #26759

Change from

$(QUIET)$(SED) 's/^\(   \* - \)\([[:print:]]\+\)$$/\1:spelling:ignore:`\2`/' $@ > $(TMP_FILE_3)

To

$(QUIET)$(SED) 's/^\(   \* - \)\([[:print:]]\{1,\}\)$$/\1:spelling:ignore:`\2`/' $@ > $(TMP_FILE_3)

Click to view the simulation of the Issue in commands

╰─$ uname -a ; which sed 
Darwin <MACBOOK_NAME> Darwin Kernel Version 22.5.0: Thu Jun  8 22:22:19 PDT 2023; root:xnu-8796.121.3~7/RELEASE_ARM64_T8103 arm64
/usr/bin/sed
╰─$ pwd
<PATH_TO_CILLIUM_FORK>/cilium
╰─$ sed 's/^\(   \* - \)\([[:print:]]\+\)$/\1:spelling:ignore:\2/' Documentation/helm-values.rst > helm-values.sed | grep "spelling"   
╭─is@CDT-MB-20200016 ~/Documents/Personal-GitHub/cilium ‹feat/enable-podsecuritycontext-on-spire-server●› 
╰─$ echo $?                                                                                                                            1 ↵
1

Click to View the change working

╰─$ sed 's/^\(   \* - \)\([[:print:]]\{1,\}\)$/\1:spelling:ignore:`\2`/' Documentation/helm-values.rst > helm-values_local.sed | grep -i "spelling" | head -n 5
   * - :spelling:ignore:`Key`
   * - :spelling:ignore:`MTU`
   * - :spelling:ignore:`affinity`
   * - :spelling:ignore:`agent`
   * - :spelling:ignore:`agentNotReadyTaintKey`
╰─$ echo $?
0

[qmonnet]

/test

[qmonnet]

Looks good, thanks a lot for this!

Here's a nice doc with differences between BSD sed (default on macOS) and GNU sed, for future reference. Indeed, the \+ syntax is not supported in the former.

I validated that the new syntax still works as expected on Linux.