Fix FPP syntax in HelloWorld docs

[sobkulir]

Originating Project/Creator	JPL Fprime
Affected Component
Affected Architectures(s)
Related Issue(s)
Has Unit Tests (y/n)	n/a
Builds Without Errors (y/n)	n/a
Unit Tests Pass (y/n)	n/a
Documentation Included (y/n)	y

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Change Description

When trying to build the HelloWorld project, I ran into an error when executing fprime-util impl because the docs contained a syntax error.

Rationale

Make the HelloWorld fpp example buildable out-of-box.

Testing/Review Recommendations

I ran fprime-util impl without problems after my change. Altough fpp-check didn't pass:

user@tpad:/app/MyComponents/HelloWorld$ fpp-check < HelloWorld.fpp
fpp-check
stdin: 41.9
        time get port timeCaller
        ^
error: undefined symbol Fw

I'm very new to fprime so I'm not sure if this is relevant.

Future Work

[thomas-bc]

You are correct, there seem to be a syntax error. Thank you for contributing!