remove return(x) from end of function

[Melissa-Karp]

Addresses issue #116 to remove last return statements.

[sbreitbart-NOAA]

spelling::spell_check_package() output: No spelling errors found.

[github-actions]

Code Metrics Report

Coverage	Code to Test Ratio	Test Execution Time
62.7%	1:0.2	1m26s

Code coverage of files in pull request scope (66.7%)

Files	Coverage
R/extract_caps_alttext.R	100.0%
R/plot_abundance_at_age.R	26.1%
R/plot_biomass.R	91.2%
R/plot_biomass_at_age.R	0.0%
R/plot_indices.R	0.0%
R/plot_landings.R	82.2%
R/plot_recruitment.R	97.0%
R/plot_recruitment_deviations.R	94.1%
R/plot_spawn_recruitment.R	100.0%
R/plot_spawning_biomass.R	90.4%
R/ss3_utils.R	0.0%
R/table_bnc.R	93.1%
R/table_indices.R	86.0%
R/table_landings.R	91.4%

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