Refactor courses to course

[AngelsandDevsLOL]

Proposed Changes

Building off the previous PR #1721 (which renamed the Course data type to CourseData and moved it into Models/Course.hs), this PR renames the Courses database table to Course. It adds a v3 migration to Database/Migrations.hs so the existing database table is renamed. It updates the Courses datatype in Database/Tables.hs to be Course, as well as updating all of the accessor functions from coursesX to courseX.

With the Course name now free from the previous PR, renaming the Courses table to Course makes the schema consistent with the rest of the table names and naming conventions.
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Screenshots of your changes (if applicable)

Type of Change

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Type	Applies?
🚨 Breaking change (fix or feature that would cause existing functionality to change)
✨ New feature (non-breaking change that adds functionality)
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🎨 User interface change (change to user interface; provide screenshots)
♻️ Refactoring (internal change to codebase, without changing functionality)	X
🚦 Test update (change that only adds or modifies tests)
📦 Dependency update (change that updates a dependency)
🔧 Internal (change that only affects developers or continuous integration)

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Questions and Comments

[coveralls]

Coverage Report for CI Build 0

Coverage increased (+0.04%) to 58.647%

Details

• Coverage increased (+0.04%) from the base build.
• Patch coverage: 6 uncovered changes across 4 files (22 of 28 lines covered, 78.57%).
• 54 coverage regressions across 3 files.

Uncovered Changes

File	Changed	Covered	%
app/Models/Course.hs	21	18	85.71%
app/Database/CourseVideoSeed.hs	1	0	0.0%
app/Database/Migrations.hs	3	2	66.67%
app/WebParsing/ArtSciParser.hs	1	0	0.0%
Total (5 files)	28	22	78.57%

Coverage Regressions

54 previously-covered lines in 3 files lost coverage.

File	Lines Losing Coverage	Coverage
app/Svg/Parser.hs	31	62.47%
app/Models/Course.hs	15	53.95%
app/MasterTemplate.hs	8	0.0%

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Coverage Stats

Relevant Lines:	3945
Covered Lines:	2376
Line Coverage:	60.23%
Relevant Branches:	964
Covered Branches:	503
Branch Coverage:	52.18%
Branches in Coverage %:	Yes
Coverage Strength:	164.33 hits per line

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💛 - Coveralls