Reorganize code for setting hosts, remove plot functions.

[maciekbanas]

Reorganizing hosts with new user functions, new host subclasses, organizing host code into functions, moving methods, optimizing token checks (moving them from engine to host class), changing idea of setting up engines (no iteration, but explicit set up of engine), cleaning code from supportive methods. Adjust tests: new test host classes.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 88.98305% with 39 lines in your changes are missing coverage. Please review.

Project coverage is 80.85%. Comparing base (1081673) to head (32491d2).
Report is 238 commits behind head on devel.

❗ Current head 32491d2 differs from pull request most recent head 71c68b3. Consider uploading reports for the commit 71c68b3 to get more accurate results

Files	Patch %	Lines
R/test_helpers.R	41.66%	21 Missing ⚠️
R/GitHost.R	92.99%	11 Missing ⚠️
R/EngineRestGitLab.R	70.00%	3 Missing ⚠️
R/EngineGraphQL.R	50.00%	1 Missing ⚠️
R/EngineGraphQLGitHub.R	66.66%	1 Missing ⚠️
R/GitHostGitHub.R	97.72%	1 Missing ⚠️
R/GitHostGitLab.R	98.33%	1 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##            devel     #383      +/-   ##
==========================================
+ Coverage   75.40%   80.85%   +5.44%     
==========================================
  Files          12       15       +3     
  Lines         992     2230    +1238     
==========================================
+ Hits          748     1803    +1055     
- Misses        244      427     +183     

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[marcinkowskak]

When trying to set connection I get error:

> git_stats <- create_gitstats() %>%
+   set_github_host(
+     orgs = c("r-world-devs", "openpharma")
+   ) %>%
+   set_github_host(
+     host = "github.roche.com",
+     orgs = "RWDScodeshare"
+   ) %>%
+   set_gitlab_host(
+     host = "code.roche.com",
+     orgs = "RWDInsightsEngineering"
+   )
ℹ Using PAT from GITHUB_PAT envar.
ℹ Your search parameter set to [org].
ℹ Checking passed organizations...
✔ Set connection to GitHub.
ℹ Using PAT from GITHUB_PAT_ROCHE envar.
ℹ Your search parameter set to [org].
ℹ Checking passed organizations...
✔ Set connection to GitHub.
Error in `purrr::map_vec()`:
! `out[[1]]` must have size 1, not size 7.
Run `rlang::last_trace()` to see where the error occurred.
> rlang::last_trace()
<error/vctrs_error_assert_size>
Error in `purrr::map_vec()`:
! `out[[1]]` must have size 1, not size 7.
---
Backtrace:
     ▆
  1. ├─... %>% ...
  2. ├─GitStats::set_gitlab_host(., host = "code.roche.com", orgs = "RWDInsightsEngineering")
  3. │ └─gitstats_obj$set_gitlab_host(...) at GitStats/R/gitstats_functions.R:74:3
  4. │   └─GitHostGitLab$new(...) at GitStats/R/GitStats.R:89:7
  5. │     └─GitStats (local) initialize(...)
  6. │       └─super$initialize(orgs = orgs, repos = repos, token = token, host = host) at GitStats/R/GitHostGitLab.R:15:7
  7. │         └─private$set_token(token) at GitStats/R/GitHost.R:26:7
  8. │           └─private$set_default_token() at GitStats/R/GitHost.R:249:9
  9. │             └─private$test_token(token) at GitStats/R/GitHost.R:404:7
 10. │               └─private$check_token_scopes(response, token) at GitStats/R/GitHost.R:428:9
 11. │                 └─... %>% unlist() at GitStats/R/GitHostGitLab.R:102:7
 12. ├─base::unlist(.)
 13. ├─dplyr::select(., scopes)
 14. ├─dplyr::filter(., date == max(date))
 15. └─purrr::map_vec(...)
Run rlang::last_trace(drop = FALSE) to see 6 hidden frames.

[marcinkowskak]

Left some minor comments regarding documentation