Update gitignore to exclude build data

[efiacor]

Exclude build files from git

# Hugo
.hugo*
resources/

# nodejs
package-lock.json
node_modules/

[efiacor]

/assign @johnbelamaric @henderiw @liamfallon

[efiacor]

/assign @CsatariGergely

[nephio-prow]

@efiacor: GitHub didn't allow me to assign the following users: CsatariGergely.

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/assign @CsatariGergely

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[liamfallon]

/lgtm
/approve

[tliron]

/lgtm
/approve

[nephio-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: CsatariGergely, liamfallon, tliron

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