fix: made install_protoc.sh compatible with wget2

[Al-Pragliola]

fixes #254

Description

Switches paths from relative to absolute for wget and any other command that uses it, to make it work with wget and wget2.

How Has This Been Tested?

I tested this on my local machine by running make bin/protoc, and also by building the docker image.

Merge criteria:

• The commits and have meaningful messages; the author will squash them after approval or will ask to merge with squash.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work

[Al-Pragliola]

cc: @tarilabs

[tarilabs]

/lgtm

thanks @Al-Pragliola let's wait for the tests to complete then I believe we can quickly merge this one

[tarilabs]

tested locally on Mac, working

/approve

[google-oss-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: tarilabs

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [tarilabs]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment